Out of Nothing: An Emergent Universe

[Stormer0628]

Schrödinger’s Fridge

Heat flows from hot things to cold things. That’s common sense. It’s also one way to state the second law of thermodynamics, which is notoriously one of the universe’s strictest rules.

In the nanoscale world ruled by quantum mechanics, however, causing heat to flow backwards may be as easy as making an observation.

According to a theoretical paper published in Nature Quantum Materials, by Angel Rubio of the Universida del Pais Vasco in San Sebastian, Spain, and colleagues, this is yet another way in which common sense goes out the window in the quantum realm.

“Initially we thought it was an error,” says Rubio. “We didn’t expect there was going to be a complete change of flow.”

The researchers designed a tiny device comprising two small groups of atoms, both kept at a constant temperature and connected to each other by two wires. In normal circumstances, heat will flow from the hotter side to the cooler one, and – unless an electric field is applied – no electrons will move around in the wires.

However, if a single point on one of the wires is observed, Rubio’s team calculated that everything will change. Depending on which point is observed, the flow of heat can be strengthened, weakened, or even reversed. At some points, observation will also cause a current of electrons to begin circulating in the wires.

(‘Observation’ in the quantum mechanics sense is not quite the same as having a peek: it means an interaction between the test system and some external device that can measure the state of the system at a certain point.)

This certainly seems odd, but Rubio is at pains to convey that nothing untoward is happening: there is no “infringement of any fundamental theorem of physics nor is energy created out of nothing”.

The secret, according to the paper, is that the observation allows a “purely quantum coherent heat flow” to occur. This means that, while heat flows uphill inside the test device, it is balanced out by heat flows in the larger system of the device-plus-observer.

The researchers relate the process to what are known in thermodynamics as “dissipative structures” -- temporary forms of organisation that help imbalances of heat or energy even out more quickly. (Examples of dissipative structures or systems include cyclones, lasers and all living things.)

It’s a fascinating result with implications for the study and control of nanoscale devices, but any applications are still a long way off.

“We have proposed a simple model and the theory can be easily verified,” says Rubio. “Carrying out this process experimentally would be another matter.”


SOURCE

 

[Stormer0628]

The Multiverse Is Inevitable, And We're Living In It

Imagine that the Universe we observe, from end-to-end, is just a drop in the cosmic ocean. That beyond what we can see, there's more space, more stars, more galaxies, and more everything, for perhaps countless billions of light years farther than we'll ever be able to access. And that as large as the unobservable Universe is, that there are again innumerably more Universes just like it — some larger and older, some smaller and younger — dotted throughout an even larger spacetime. As rapidly and inevitably as these Universes expand, the spacetime containing them expands even more quickly, driving them apart from one another, and ensuring that no two Universes will ever meet. It sounds like a fantasy picture: the scientific idea of a Multiverse. But if the science we accept today is correct, it's not only a valid idea, it's an unavoidable consequence of our fundamental laws.

The idea of the Multiverse has its roots in the physics required to describe the Universe that we see and inhabit today. Everywhere we look in the sky, we see stars and galaxies, clustered together in a great cosmic web. But the farther away in space we look, the farther back in time we look as well. The more distant galaxies are younger, and hence less evolved. Their stars have fewer heavy elements in them, they appear smaller as fewer mergers have happened, there are more spirals and fewer ellipticals (which take time to form from mergers), and so on. If we go all the way to the limits of what we can see, we find the very earliest stars in the Universe, and then a region of darkness beyond that, where the only light is the leftover glow from the Big Bang.

But the Big Bang itself — occurring everywhere at once some 13.8 billion years ago — wasn’t the start of space and time, but rather the start of our observable Universe. Before that, there was an epoch known as cosmic inflation, where space itself expanded exponentially, full of energy inherent to the fabric of spacetime. Cosmic inflation is itself an example of a theory that came along and superseded the one that came before it, in that it:

1. Was consistent with all the successes of the Big Bang and encompassed all of modern cosmology.
2. Explained a number of problems that the Big Bang couldn’t address, including why the Universe was the same temperature everywhere, why it was so spatially flat, and why there were no leftover high-energy relics like magnetic monopoles.
3. And it made many distinct new predictions that could be tested observationally, most of which have been confirmed.

There’s also, however, one consequence that inflation predicts that we do not know whether we can confirm or not: the Multiverse.

The way inflation works is by causing space to expand at an exponential rate. This takes whatever existed before the hot Big Bang and made it much, much, much larger than it was previously. So far, so good: this explains how we get such a uniform, large Universe. When inflation ends, that Universe gets filled with matter and radiation, which is what we see as the hot Big Bang. But here’s where it gets weird. In order for inflation to end, whatever quantum field is responsible for it has to roll from the high-energy, unstable state that drives inflation down into a low-energy, equilibrium state. That transition, and "rolling" down into the valley, is what causes inflation to come to an end, and create the hot Big Bang.

But whatever field is responsible for inflation, like all other fields that obey the laws of physics, must be an inherently quantum field in nature. Like all quantum fields, it's described by a wavefunction, with the probability of that wave spreading out over time. If the value of the field is rolling slowly-enough down the hill, then the quantum spreading of the wavefunction will be faster than the roll, meaning that it's possible — even probable — for inflation to wind up farther away from ending and giving rise to a Big Bang as time goes on.

Because space is expanding at an exponential rate during inflation, this means that exponentially more regions of space are being created as time goes on. In a few regions, inflation will come to an end: where the field rolls down into the valley. But in others, inflation will continue on, giving rise to more and more space surrounding each and every region where inflation ends. The rate of inflation is far more rapid than even the maximum rate of expansion of a matter-and-energy-filled Universe, so in very short order, the inflating parts take over everything. According to the viable mechanisms that give us enough inflation to produce the Universe we see, there are many more regions of space surrounding our own — where inflation did end — where inflation doesn’t end right away.

This is where the phenomenon known as eternal inflation comes from. Where inflation ends, we get a hot Big Bang and a Universe — of which we can observe part of the one we’re in — very much like our own. (Denoted by the red “X” above.) But where inflation doesn’t end, that produces more inflating space, which gives rise to some regions that will have hot Big Bangs causally disconnected from our own, and other regions that will continue to inflate. And so on.

This picture, of huge Universes, far bigger than the meager part that's observable to us, constantly being created across this exponentially inflating space, is what the Multiverse is all about. It's important to recognize that the Multiverse is not a scientific theory on its own. It makes no predictions for any observable phenomena that we can access from within our own pocket of existence. Rather, the Multiverse is a theoretical prediction that comes out of the laws of physics as they’re best understood today. It’s perhaps even an inevitable consequence of those laws: if you have an inflationary Universe governed by quantum physics, this is something you’re pretty much destined to wind up with.

It's possible that our understanding of the state before the hot Big Bang is incorrect, and that our ideas about inflation are completely wrong for this application. If that's the case, then the existence of a Multiverse isn't a foregone conclusion. But the prediction of an eternally inflating state, where an uncountably large number of pocket Universes are continuously born and driven inextricably apart from one another, is a direct consequence of our best current theories, if they're correct.

What is the Multiverse, then? It may go well beyond physics, and be the first physically motivated “metaphysics” we’ve ever encountered. For the first time, we’re understanding the limits of what our Universe can teach us. There is information we need, but that we'll never obtain, in order to elevate this into the realm of testable science. Until then, we can predict, but neither verify nor refute, the fact that our Universe is just one small part of a far grander realm: the Multiverse.

Astrophysicist and author Ethan Siegel is the founder and primary writer of Starts With A Bang! His books, Treknology and Beyond The Galaxy, are available wherever books are sold.



SOURCE

 

[Stormer0628]

Re: The Multiverse Is Inevitable, And We're Living In It

The combined use of gravitational wave detectors and all kinds of telescope all over the world, involving 70 laboratories, 7 satellite-based telescopes over 7 continents, with a single paper coauthored by no less than 4600 scientists, in what is billed as multimessenger collaboration, heralds a new era in astronomy, physics, and all science.​

Some 130 million years ago, in a nearby galaxy, two neutron stars collided. The cataclysmic crash produced gravitational waves, ripples in the fabric of spacetime that traveled across the universe. On August 17, along with hundreds of other collaborators around the globe, assistant professor of physics Marcelle Soares-Santos finally got to see them.

The finding remained under wraps until today when it was officially announced by the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo, the umbrella organizations overseeing the worldwide search for gravitational waves. Researchers are heralding the discovery as the dawn of a new era of scientific discovery, when analyzing gravitational waves will offer answers to some of the biggest mysteries in cosmology.

In the short term, we will gain new insights into neutron stars, which occur when giant stars 10 to 30 times as big as the sun collapse into objects about the size oft he greater Boston metropolitan area. But over a longer period, gravitational waves may explain the universe’s continued expansion and the composition of dark energy, an elusive, mysterious substance that makes up roughly 70 percent of the universe.

“This is a whole new window into the universe,” Soares-Santos said. “This is beyond my wildest dreams.”

Soares-Santos arrived at Brandeis this year after working for more than a decade at the Fermi National Accelerator Laboratory, part of the U.S. Department of Energy. Every winter, she has journeyed to a mountaintop in northern Chile to peer at the stars through the Cerro Tololo Inter-American Observatory’s telescope,one of the most powerful in the world.

A year ago, LIGO scientists also reported they’d discovered gravitational waves,but those were from the merger of two black holes, not neutron stars. The signals for black hole gravitational waves usually last less than a second while those from neutron stars persist for as long as a minute, providing reams more data.

In addition, the black hole research involved recording the vibrations gravitational waves cause as they distort spacetime. (They sound like a series of small thumps.)But this time around, in addition to capturing these vibrations, Soares-Santos and her colleagues in Chile captured the waves’ optical signal. An image yields far more precise information than the sound recordings.

“The optical signal lets us do the equivalent of actually going there and looking at the neutron star merger,”Soares-Santos said. "Hopefully, over time, we will be able to understand the internal dynamics of neutron stars much better. One of the things we’ve always wondered is how the heavy elements in the universe were created. We can explain the large amounts of iron, but any element with a higher atomic weight — gold and silver, for example— we don’t know for sure how they were created. You really need a high-energy event for those elements to be produced in the high quantities present in the universe," she added.

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Four times in the past 2 years, physicists working with mammoth gravitational wave detectors have sensed something go bump in the night, sending invisible ripples through spacetime. Today, they announced the detection of a fifth such disturbance—but this time astronomers saw it, too, at every wavelength of light from gamma radiation to radio waves. Just as physicists had predicted, the unprecedented view of the cosmic cataclysm—in which two superdense neutron stars spiraled into each other—brought with it a cornucopia of insights, each of which by itself would count as a major scientific advance.

"It's really a big gift that nature has given us," says Alessandra Corsi, a radio astronomer at Texas Tech University in Lubbock. "It's a life-changing event."

At 12:41 universal time on 17 August, physicists with three massive instruments—the twin 8-kilometer-long detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Hanford, Washington, and Livingston, Louisiana, and the 6-kilometer Virgo detector near Pisa, Italy—spotted waves unlike any seen before. The four previous events lasted for, at most, a few seconds, with gravitational waves rippling at frequencies of tens of cycles per second. The new siren sang for 100 seconds at frequencies climbing to thousands of cycles per second. Whereas the earlier signal came from pairs of huge black holes quickly spiraling into each other, the new signal revealed lighter neutron stars, 1.1 and 1.6 times as massive as the sun, twirling inexorably together, researchers announced in parallel press conferences in Washington, D.C., and Garching, Germany.

The gravitational waves marked the beginning of a spectacular light show. Because black holes are the gravitational fields left behind when very massive stars collapse to infinitesimal points, they contain no matter that might radiate light when an isolated pair of them merges. In contrast, neutron stars are the dead cores left behind when slightly smaller stars explode in supernovas, and they consist of the nearly pure neutrons in the densest matter there is. When such orbs collide, they should spew debris glowing with light of all wavelengths.

That's exactly what happened. Two seconds after the gravitational signal, which only the automated "trigger" of the Hanford detector initially noticed, NASA's orbiting Fermi Gamma-ray Space Telescope picked up a blast of high-energy photons called a gamma ray burst. Within minutes, researchers at the Livingston and Virgo detectors confirmed the gravitational signal in their data. Still, it took LIGO the better part of an hour to issue a detailed alert, says Julie McEnery, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and a member of the Fermi team. McEnery says she found out about the gravitational signal as a coy rumor from a colleague who works on both Fermi and LIGO. "A half-hour [after the Fermi alert] we got an email that said, 'This gamma ray burst has an interesting friend,'" she says.

Because all three gravitational-wave detectors saw the signal, physicists could triangulate and locate the source to within a 30-square-degree patch of sky—about 60 times the size of the moon and much more precise than Fermi’s localization. Astronomers swiveled telescopes large and small to the spot in the constellation Hydra. The search got off to a slow start because that part of sky was in daylight for many observatories. But within hours, five groups had identified a new source of light in the periphery of galaxy NGC 4993, which they watched fade from bright blue to dim red in a matter of days. Nearly 2 weeks later, the source began to emit x-rays and radio waves.

In the end, more than 70 observatories studied the event. "This is first time we have a 3D IMAX view of an astronomical event," says Laura Cadonati, a physicist at the Georgia Institute of Technology in Atlanta and deputy spokesperson for the LIGO collaboration.

The combination of gravitational waves and electromagnetic observations scored at least three significant advances. First, it explains the origins of some gamma ray bursts, the second most powerful known events in the cosmos other than merging black holes. Since the 1990s, theorists have thought that bursts shorter than two seconds originate when neutron stars merge to create a black hole. (Longer bursts, lasting minutes, are thought to spring from the collapse of individual massive stars.) The new result clinches the explanation for short bursts, says Peter Mészáros, a theorist at Pennsylvania State University in State College. "It's tremendous," he says. "If you have gravitational waves with a burst you know it has to come from a double neutron star."

Second, the event reveals a hypothesized object called a kilonova, because it briefly shines thousands of times brighter than an ordinary nova. As two neutron stars twirl together and rip each other apart, they should expel neutron-rich atomic nuclei, forming a shroud of matter totaling a few percent of a solar mass. Those nuclei beef up by gobbling neutrons in rapid succession and then quickly change their chemical identities through radioactive decay. That so-called r-process—or rapid neutron capture process—should make the shroud glow for a few days, and its light should be reddened by heavy elements that soak up blue wavelengths. That's just what astronomers saw, says Brian Metzger, a theorist at Columbia University. "It's stunning. All of a sudden the curtain lifts and what we see looks pretty close to what we expected."

The observation of a kilonova scores a third advance by solving a long-standing puzzle in nuclear physicists: the origin of half the elements heavier than iron, including silver, gold, and platinum. Nuclear physicists have long thought that those elements are generated in r-process, but haven't known where in the cosmos that happens—whether in the collapse of single stars or in merging neutron stars. The new find shows that some, and quite possibly all, of the mystery elements come from neutron-star death spirals. "For me, as a nuclear physicist, this is an extremely important result," says Witold Nazarewicz a theorist at Michigan State University in East Lansing, where experimenters are building a $730 million accelerator, in part to study the r-process.

The neutron star merger presents some puzzles of its own. For example, the gamma rays were relatively faint, even though the burst was closer than any previously measured short burst by a factor of 10, McEnery notes. That could be because researchers saw the merger from a funny angle, she says. A gamma ray burst is thought to emerge when jets of hot matter moving at near–light-speed shoot out along the rotational axis of the newborn black hole, beaming radiation into space like a lighthouse. In this case, observers on Earth may not be looking right down the jet but may be viewing it from a slight angle, McEnery says—astronomers’ first off-axis view of an astrophysical jet.

The long lag before astronomers began to pick up radio and x-ray emissions supports that picture, says Raffaella Margutti, an astrophysicist at Northwestern University in Evanston, Illinois, who studied the event with NASA's orbiting Chandra X-ray Observatory. The radio and x-ray signals come from the jet, which at first would have beamed them too narrowly along its axis to be seen from Earth. As the jet slowed, however, radiation would emerge at wider angles, making the signals detectable off-axis.

Ever since LIGO announced the first gravitational-wave event in early 2016, networks of small telescopes around the world have been poised to detect an “optical counterpart.” The race touched off by this latest event was won by Ryan Foley of the University of California (UC), Santa Cruz, and colleagues. They use 1-meter telescopes on Mount Hamilton in California and on Cerro Las Campanas in Chile to follow up LIGO/Virgo alerts. At 23:33 universal time, 10 hours and 52 minutes after the gravitational waves arrived, the team used the telescope in Chile to snap an image of NGC 4993, and Charles Kilpatrick, a postdoc at UC Santa Cruz, saw a bright spot not visible in archival images of the galaxy. "Found something," he remarked coolly in an online messaging exchange. Within the 40 minutes, four other teams had independently discovered the same optical object.

Rumor spread almost instantly over the internet. Within days, other scientists and journalists knew the outlines of the discovery, and the LIGO and Virgo teams struggled to keep a lid on the news until today's press event. That was no easy task, given the fact that astronomers tend to work in small, highly competitive teams, says Andrew Howell, an astronomer at UC Santa Barbara, and staff scientist with the Las Cumbres Observatory, which also tracked the event. Used to working as a huge team, LIGO physicists “were absolutely unprepared for the chaos that is the astronomical community," he says.

Nonetheless, astronomers and astrophysicists came together to write a single compendious paper about the event. It has been submitted to The Astrophysical Journal Letters and some researchers say it has 4600 authors—roughly one-third of all astronomers. In addition, individual groups are publishing dozens of other papers in Science, Nature, and other journals, many concurrently with the announcement.

With one spectacular event in the bag, the era of gravitational wave astronomy has begun. The next step is simply to see more such events and begin to do statistical analyses on them, astronomers say. But for the moment, the entire community is basking in the glow of the discovery and the stunning success of its models. "Sometimes I wonder whether we're all just mucking around," Howell says. "It's moments like this that reassure me that science works."


SOURCES

SCIENCEMAG

BRANDEIS





UPDATED




HISTORY

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NOTE: well, i think they just shut down the source. it's the only one that had anything about the much touted forthcoming announcement from LIGO scientists involved in the project. it's a curious thing, really, since there had been no official word from anywhere in the internet yet. let's see if this holds.

stand by for updates.


UPDATE 02

Still nothing, but there's palpable excitement coursing through the internet, like here.

This is getting weird....


UPDATE 03
Well, here's a livestream...

and yes ... the post is spot on...

who would have thought symbianize would get it 4-5 hours before the official announcement....

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Think about it, folks: outside of the scientists involved in this, you saw it first here in SB, hours ahead of the official press conference broadcast all over the world.

Now news all over the world is about this neutron star collision. Aren't you glad to be alive to see all of these?

And think of this: if you are wearing a piece of gold jewelry, take a good, hard look at it and consider this: you are likely to be wearing the celestial debris of a cataclysmic stellar collision, a collision so devastating that it literally shook the universe.

According to Stefan Ballmer, who helped build the Advanced LIGO detectors, the amount of gold produced by this one collision rivals the mass of our Moon:

"If you’re wondering how much the gold we saw being made is worth? About $10 octillion— $10,000,000,000,000,000,000,000,000,000—at today’s prices."​

For the first time, we now have visual confirmation that the heaviest elements in the periodic table arise from neutron star collisions.

 

[Stormer0628]

Re: The Multiverse Is Inevitable, And We're Living In It

You've no doubt heard that the Universe itself has been around for 13.8 billion years since the Big Bang, and that scientists are extremely confident of that figure. In fact, the uncertainty on that figure is under 100 million years: less than 1% of the estimated age. But science has been wrong in the past. Could it be wrong again, about this? That's the question of John Deer, who asks:

Lord Kelvin estimated the age of the Sun between 20 and 40 million years because his model didn't (couldn't) include quantum mechanics and relativity. How probable is it we're doing a similar mistake when looking at the universe at large?​

Let's take a look at the historical problem, and then jump to the modern-day situation to understand more.

Back at the end of the 19th century, there was a huge controversy over the age of the Universe. Charles Darwin, looking at the evidence from biology and geology, concluded that the Earth itself must be at least hundreds of millions, if not billions of years old. But Lord Kelvin, looking at the stars and how they worked, concluded that the Sun itself needed to be far younger. The only reactions he knew of were chemical reactions, such as combustion, and gravitational contraction. The latter turns out to be how white dwarf stars get their energy, but to put out as much energy as the Sun would imply a lifetime of tens of millions of years only. The two pictures didn't add up.

Of course, this was resolved decades later, with the discovery of nuclear reactions, and the application of Einstein's E = mc2 to the hydrogen fusion that occurs in the Sun. When the calculations were fully worked out, we realized that the Sun's lifetime would be something more like 10-12 billion years, and that we were about 4.5 billion years into our Solar System's existence. The ages of the Sun (from astronomy), the Earth (from geology), and life (from biology) all lined up in a consistent, coherent picture.

We have two ways to calculate the age of the Universe today: to look at the ages of the individual stars and galaxies within it, and to look at the physics of the expanding Universe. The stars themselves are the less precise metric, as we can only view them at one instant in time, and then extrapolate stellar evolution backwards. This is useful when we have large populations of stars, like globular clusters, but is more difficult for individual stars. The method is simple: when large populations of stars are born together, they come in all different sizes and colors, from hot, massive, and blue, to cool, small, and red. As time goes on, the more massive stars burn through their fuel the fastest, and so they begin to evolve and, later, die.

If we look at the survivors, therefore, we can date how old a population of stars is. Many globular clusters have ages in excess of 12 billion years, with some even exceeding 13 billion years. With advances in both observational techniques and capabilities, we've measured not only the carbon, oxygen, or iron content of individual stars, but by using the radioactive decay abundances of uranium and thorium, in conjunction with the elements created in the Universe's first supernovae, we can date their ages directly.

The star HE 1523-0901, which is about 80% of the Sun's mass, contains only 0.1% of the Sun's iron, and is measured to be 13.2 billion years old from its radioactive element abundances. In 2015, a set of nine stars near the Milky Way's center were dated to have formed 13.5 billion years ago: just 300,000,000 years after the Big Bang, and before the initial formation of the Milky Way, with one of them having has less than 0.001% of the Sun's iron: the most pristine star ever found. And controversially, there's the Methuselah star, which comes in at a surprising 14.46 billion years, albeit with a large uncertainty of around 800 million years.

But there's a better, more precise way to measure the age of the Universe: through its cosmic expansion.

The four possible fates of our Universe into the future; the last one appears to be the Universe we live in, dominated by
dark energy. What's in the Universe, along with the laws of physics, determines not only how the Universe evolves, but how old it is​

By measuring what's in the Universe today, how distant objects appear to move, and how the light from them behaves nearby, at intermediate distances, and for the greatest distances observable, we can reconstruct the expansion history of the Universe. We now know our Universe consists of approximately 68% dark energy, 27% dark matter, 4.9% normal matter, 0.1% neutrinos, and 0.01% radiation, today. We also know how these components evolve in time, and that the Universe obeys the laws of General Relativity. Combine those pieces of information, and a single, compelling picture of our cosmic origins emerge.

Three different types of measurements, distant stars and galaxies, the large scale
structure of the Universe, and the fluctuations in the CMB, tell us the expansion history of the Universe.​

For a few seconds, the Universe was an ionized mess of particles and antiparticles, which eventually cooled and allowed the formation of leftover atomic nuclei after a few minutes. After 380,000 years, the first stable, neutral atoms formed. Over tens to hundreds of millions of years, gravitational attraction brought this matter together into stars and then galaxies. And over billions of years further, galaxies merged and grew to give us the Universe we see today. With the data collected from a variety of sources, including the cosmic microwave background, the large-scale clustering of galaxies, distant supernovae, and baryon acoustic oscillations, we arrive at a single, compelling picture: a Universe that's 13.8 billion years old today.

The cosmic history of the entire known Universe shows that we owe the origin of all the matter within it, and all the light, ultimately, to the end of inflation and the beginning of the Hot Big Bang. Since then, we've had 13.8 billion years of cosmic evolution, a picture confirmed by multiple sources.​

There are some uncertainties that go beyond what gets reported by, say, Wikipedia, which quotes our Universe as being 13.799 ± 0.021 billion years old. That 21 million year uncertainty could easily get five-to-ten times as large if there's a systematic mistake that's been made somewhere. There's presently a controversy over the expansion rate (the Hubble constant) today, with the CMB indicating it's closer to 67 km/s/Mpc, while stars and supernovae point towards a figure more like 74 km/s/Mpc (*the latest data from the neutron stars collision indicate it is somewhere in the middle, at 70 km/s/Mpc). There are uncertainties in the dark matter/dark energy mix, with some measurements favoring a ratio as low as 1:2, while others favor 1:3 or anything in between. Depending on the resolution to these puzzles, it's conceivable that the Universe could be as young as 13.6 billion years, or as old as 14 billion.

What's unlikely, however, is that there's going to be a major revision of this 13.8 billion year figure. Even if there is more fundamental physics than the forces, particles, and interactions that we know of, they are unlikely to change the physics of how stars work, how gravity works over time, how the Universe expands, or how radiation/matter/dark energy make up our Universe. These things are well-measured, well-constrained, and as well-understood as one could reasonably ask for. Even if dark energy evolves, fundamental constants like G or c or h change over time, or the Standard Model particles can be further broken up, the age of the Universe won't change by very much from the Big Bang until the present.

Revisions and surprises may certainly be coming, but when it comes to the age of the Universe, after millennia of wondering, humanity finally has an answer it can trust.





SOURCE

 

[Stormer0628]

We Shouldn't Be Here

Symmetry. Such a simple, unassuming word—yet, in all the universe, there's not another term or concept that is more profoundly connected and critical to our existence.

Why are we here, anyway? No, not in the what’s-the-meaning-of-it-all sense, but why haven’t matter and antimatter completely obliterated each other, the universe and us? In nature, two identical things that are 180° out of phase with each other — as matter and antimatter seem to be — cancel each other out. So, um, why are we here?

In audio, for example, two identical sound waves that are out of phase in this way produce silence:

So even if, say , you’re talking about identical recordings of something loud like a car horn, you get:

honk +

honk =

no honk​

So we’ve got a problem with matter and antimatter not doing this, or rather, we should have a problem. Physics’ standard model says that when the universe came into being at the Big Bang, an equal amount of matter and antimatter was generated that should have — in our current understanding — wiped each other out, preventing the universe as we know it from forming.

Scientists have been thinking there must be something we haven’t come across yet that makes matter and antimatter not truly identical. A just-released study in the journal Nature reveals the frustrating outcome of a recent search for that difference at CERN. Christian Smorra, a physicist with their Baryon–Antibaryon Symmetry Experiment (BASE) collaboration, says, “An asymmetry must exist here somewhere but we simply do not understand where the difference is,” because, “All of our observations find a complete symmetry between matter and antimatter, which is why the universe should not actually exist.”

Previously, scientists have tried to find some difference other than polarity in matter and antimatter, measuring their mass and electric charge, and with a study last year of the properties of hydrogen and anti-hydrogen atoms: Nothing.

One aspect scientists haven’t been able to compare precisely before were the magnetic moments of the proton and antiproton — there’s been simply no way to do it. ( A magnetic moment is a measurement of an object's tendency to align with a magnetic field.) So ten years back, a team at BASE began trying to work out how they could.

BASE’s antiproton decelerator at CERN (STEFAN SELLNER, FUNDAMENTAL SYMMETRIES LABORATORY, RIKEN, JAPAN)​

In 2014, BASE announced their first breakthrough: They could measure the magnetic moment of protons by trapping them in a magnetic field and inducing quantum jumps in the field’s spin using a separate magnetic field.

Tricky as that was, performing the same measurement in antiprotons was even thornier, since antiprotons are immediately destroyed when they come in contact with regular matter, such as one of the scientists’ containers.

The team figured out how to increase the the lifespan of antiprotons by holding them in an innovative, purpose-built iridium-sealed copper cylinder.

The chamber is said to look not unlike a Pringle’s can. (SELLNER, ET AL)​

CERN describes the operation of the chamber, the most effective antimatter container ever made:

The reservoir trap is inside a cylinder with a volume of 1.2 litres. The particles are trapped by two overlying magnetic and electric fields, which keep the particles in a small volume in the centre of the trap. On one side of the trap there is a metal window, thin enough to allow the antiprotons to pass through but strong enough to ensure complete insulation from the outside. All the other sides of the trap are made from solid copper. The cylinder is then cooled to about 6 K (-267 °C) with liquid helium, so that an almost perfect vacuum is created.​

A stream of antiprotons was fired into the frigid container on November 12, 2015, and the team was able to hold them there for an impressive 405 days.

During that time, they were able to run the magnetic moment measurement procedure they used for protons.

The new research documents the results of their efforts: the magnetic moment of an antiproton, out to nine places, is −2.7928473441 μN (μN is the symbol for micronewton force). And guess what? That’s identical to the magnetic moment of a proton. Could the difference lie somewhere beyond nine mathematical places?

Maybe, but, as Stefan Ulmer, leader of the BASE team avers, “This result is the culmination of many years of continuous research and development, and the successful completion of one of the most difficult measurements ever performed in a Penning trap instrument.”

So, for now, the puzzle continues, and scientists will keep sleuthing in hopes of solving this fundamental mystery : Why are we here?




SOURCE

 

[Dongxkie21]

Re: Half the universe’s missing matter finally found

salamat sa thread very informative at graveh talaga ang mundo ang daming di pa natin natutuklasan hanggang ngayon...

 

[Stormer0628]

Re: Half the universe’s missing matter finally found

salamat sa thread very informative at graveh talaga ang mundo ang daming di pa natin natutuklasan hanggang ngayon...

Welcome. Yan talaga ang point ng thread na to, to share the latest information in core sciences that not only shed light on the universe, but also give us deep insight about our part in it. Things like symmetry research, dark matter, dark energy, and strange physics coming out of the labs are all fun to watch as they unfold. There are a lot of awe-inspiring discoveries out there, waiting for us to learn.

 

[Stormer0628]

Welcome and enjoy. So many developments to cover, pinipili ko lang yung pinakaimportante and somewhat easy to relate to our daily existence, kahit na theoretical, hehe. Pag medyo mahirap you can shoot questions and I or anybody might like to come up with some answer.

 

[Stormer0628]

The point of the most famous thought-experiment in quantum physics is that the quantum world is different from our familiar one. Imagine, suggested the Austrian physicist Erwin Schrödinger, that we seal a cat inside a box. The cat’s fate is linked to the quantum world through a poison that will be released only if a single radioactive atom decays. Quantum mechanics says that the atom must exist in a peculiar state called ‘superposition’ until it is observed, a state in which it has both decayed and not decayed. Furthermore, because the cat’s survival depends on what the atom does, it would appear that the cat must also exist as a superposition of a live and a dead cat until somebody opens the box and observes it. After all, the cat’s life depends on the state of the atom, and the state of the atom has not yet been decided.

Yet nobody really believes that a cat can be simultaneously dead and alive. There is a profound difference between fundamental particles, such as atoms, which do weird quantum stuff (existing in two states at once, occupying two positions at once, tunnelling through impenetrable barriers etc) and familiar classical objects, such as cats, that apparently do none of these things. Why don’t they? Simply put, because the weird quantum stuff is very fragile.

Quantum mechanics insists that all particles are also waves. But if you want to see strange quantum effects, the waves all have to line up, so that the peaks and troughs coincide. Physicists call this property coherence: it’s rather like musical notes being in tune. If the waves don’t line up, the peaks and troughs cancel each other out, destroying coherence, and you won’t see anything odd. When you’re dealing only with a single particle’s wave, on the other hand, it’s easy to keep it ‘in tune’ – it has to line up only with itself. But lining up the waves of hundreds, millions or trillions of particles is pretty much impossible. And so the weirdness gets cancelled out inside big objects. That’s why there doesn’t seem to be anything very indeterminate about a cat.

Nevertheless, wrote Schrödinger in What Is Life? (1944), some of life’s most fundamental building blocks must, like unobserved radioactive atoms, be quantum entities able to perform counterintuitive tricks. Indeed, he went on to propose that life is different from the inanimate world precisely because it inhabits a borderland between the quantum and classical world: a region we might call the quantum edge.

Schrödinger’s argument was based on the following, seemingly paradoxical fact. Although they seem magnificently orderly, all the classical laws, from Newtonian mechanics to thermodynamics to the laws of electromagnetism, are ultimately based on disorder. Consider a balloon: it is filled with trillions of molecules of air all moving randomly, bumping into one another and the skin of the balloon. Yet, when you add up all their motions and average them out, you get the gas laws, which precisely predict, for example, that the balloon will expand by a given amount when heated. Schrödinger called this kind of law ‘order from disorder’, to reflect the fact that the macroscopic regularity depends on chaos and unpredictability at the level of individual particles.

What does this have to do with life? Well, Schrödinger was particularly interested in the question of heredity. In 1944, a decade before James Watson and Francis Crick, the physical nature of genes was still mysterious. Even so, it was known that they must be passed down the generations with an extraordinary high degree of fidelity: less than one error in a billion. This was a puzzle, because one of the few other known facts about genes was that they were very small – far too small, Schrödinger insisted, for the accuracy of their copying to depend on the order-from-disorder rules of the classical world. He proposed that they must instead involve a ‘more complicated organic molecule’, one in which ‘every atom, and every group of atoms, plays an individual role’.

Schrödinger called these novel structures ‘aperiodic crystals’. He asserted that they must obey quantum rather than classical laws, and further suggested that gene mutations might be caused by quantum jumps within the crystals. He went on to propose that many of life’s characteristics might be based on a novel physical principle. In the inanimate world, as we have seen, macroscopic order commonly arises from molecular disorder: order from disorder. But perhaps, said Schrödinger, the macroscopic order we find in life reflects something else: the uncanny order of the quantum scale. He called this speculative new principle ‘order from order’.

Was he right?

The colour of your eyes, the shape of your nose, your intelligence
or propensity for disease are encoded at the quantum level​

A decade later, Watson and Crick unveiled the double helix. Genes turned out to be made from a single molecule of DNA, which is a kind of molecular string with nucleotide bases (the genetic letters) strung out like beads. That’s an aperiodic crystal in all but name. And, just as Schrödinger predicted, ‘every group of atoms’ does indeed play ‘an individual role’, with the position of even individual protons – a quantum property – determining each genetic letter. There can be few more prescient predictions in the entire history of science. The colour of your eyes, the shape of your nose, and aspects of your character, intelligence or propensity for disease are encoded at the quantum level.

And yet, the new science of molecular biology that followed Watson and Crick’s discovery remained largely wedded to the concepts of classical physics. This worked pretty well in the latter half of the 20th century, as molecular biologists and biochemists focused on things such as metabolism, which is a product of very large numbers of particles operating under the order-from-disorder principle. But as the attention of 21st‑century biology is now turning to the dynamics of ever-smaller systems – even individual atoms and molecules inside living cells – quantum mechanics is once again making its presence felt. Recent experiments indicate that some of life’s most fundamental processes do indeed depend on weirdness welling up from the quantum undercurrent of reality.

Let’s start with a few relatively peripheral examples – such as the sense of smell. The conventional theory of olfaction is that odour molecules are detected by odour receptors via a kind of lock‑and‑key mechanism inside the nose: the molecule slots into the receptor and triggers a response, like a key turning a lock. It’s a nice, intuitive theory, but it fails to account for certain puzzling observations – for example, the fact that very similarly-shaped molecules often smell different and vice versa. A revised approach suggests that, instead of shape, the receptors might be responding to molecular vibration. This idea received a further quantum twist in 1996, when the biophysicist Luca Turin proposed that vibrations might promote quantum tunnelling of electrons to open the olfactory lock. A quantum theory of smell sounds outlandish, perhaps, but evidence has recently emerged to support it: it was found that fruit flies can distinguish odorants with exactly the same shape but different isotopes of the same elements, something that is hard to explain without quantum mechanics.

Or consider this: Some birds and other animals are known to find their way by detecting the Earth’s very weak magnetic field, yet the mechanism by which they do this has been a long-standing puzzle. The problem is that it is hard to see how such a weak field can generate a signal inside an animal’s body. Further questions emerged in studies involving the European robin: the research revealed that its compass is light-dependent, and that, unlike a conventional compass, it detects the angle of magnetic field lines relative to the Earth’s surface rather than their orientation. No one had any idea why.

Then in the 1970s, the German chemist Klaus Schulten discovered that some chemical reactions produced pairs of particles that remained connected via a peculiar quantum property called entanglement. Entanglement allows distant particles to remain instantaneously connected, no matter how far apart they are: they can be flung to opposite ends of the galaxy and yet remain mysteriously correlated. Entanglement is so weird that Albert Einstein himself, who gave us black holes and warped space-time, dismissed it as ‘spooky action at a distance’. But hundreds of experiments have demonstrated that it is real.

Schulten discovered that entangled pairs of particles can be extraordinarily sensitive to both the strength and the orientation of magnetic fields. He went on to propose that the enigmatic avian compass might be using quantum-entangled particles. Hardly anyone took the idea seriously, but in 2000, Schulten wrote an influential paper with his student, Thorsten Ritz, showing how light could be used to make a quantum-entangled compass in a bird’s eye. In 2004, Ritz teamed up with the celebrated husband-and-wife ornithologists Wolfgang and Roswitha Wiltschko, and together they found compelling experimental evidence that the European robin was indeed using Einstein’s spooky action to find its way around the globe every year.

Electrons and protons vanish from one position and
rematerialise in another – a kind of teleportation​

Navigation and smell are important, no doubt, but perhaps they don’t seem very central to the business of life on Earth. So let’s go after something bigger.

Take enzymes. These are the workhorses of the living world, speeding up chemical reactions so that processes that would otherwise take thousands of years happen inside living cells in seconds. How they achieve this speed-up – often more than a trillion-fold – has long been an enigma. But now, research by Judith Klinman at the University of California, Berkeley and Nigel Scrutton at the University of Manchester (among others) has shown that enzymes can employ a weird quantum trick called tunnelling. Simply put, the enzyme encourages a process whereby electrons and protons vanish from one position in a biochemical and instantly rematerialise in another, without visiting any of the in-between places – a kind of teleportation.

This is pretty fundamental stuff. Enzymes made every single biomolecule in every cell of every living creature on the planet. They are, more than any other component (even DNA, given that some cells get by without it) the essential ingredient of life. And they dip into the quantum world to help keep us alive.

We can up the stakes still further. Photosynthesis is the most important biochemical reaction on the planet. It is responsible for turning light, air, water and a few minerals into grass, trees, grain, and, ultimately, the rest of us who eat either the plants or the plant-eaters. The initiating event is the capture of light energy by chlorophyll molecules. This light energy gets turned into electrical energy, which is then transported to a biochemical factory called the reaction centre, where it is harnessed to fix carbon dioxide and turn it into plant matter. This energy transport process has long fascinated researchers because it can be so efficient – close to 100 per cent. How is it that green leaves can transport energy so much better than our most sophisticated technologies?

Graham Fleming’s laboratory at University of California, Berkeley has been investigating this question for more than a decade, using a technique called femtosecond spectroscopy. Essentially, the team shines very short bursts of laser light at the photosynthetic complex in order to discover the path of the photon as its makes its way to the reaction centre. Back in 2007, the team investigated a bacterial system called the FMO complex, in which the photon energy has to find its way through a cluster of chlorophyll molecules. It was thought to travel as a kind of electrical particle that hopped from one chlorophyll molecule to another, much as Schrödinger’s cat might have hopped from one boulder to another across a stream. But this didn’t make complete sense. Lacking any navigational sense, most photon energy should hop aimlessly in the wrong direction, ending up in the metaphorical water. And yet, inside plants and bacteria that perform photosynthesis, nearly all packets of photon energy reach the reaction centre.

When the team shone the laser at the system, they observed a very peculiar light echo that came in beat-like waves. These ‘quantum beats’ were a sign that, instead of taking a single route through the system, the photon energy was using quantum coherence to travel by all possible routes simultaneously. Imagine if, when confronted by the stream, the famous cat somehow divided itself into lots of identical quantum-coherent cats that hop across the chlorophyll boulders by every available route to find the quickest one. Quantum beats have now been detected in many different photosystems, including those of regular plants such as spinach. It appears that the most important reaction in the biosphere is exploiting the quantum world to put our food on our table.

How does life maintain its molecular order long
enough to perform its quantum tricks in warm and wet cells?​

And if that’s not enough for you, we come at last to the very mechanisms of evolution itself. Schrödinger suggested that mutations could involve a kind of quantum jump. In their classic DNA paper, Watson and Crick proposed that they might involve nucleotide bases switching between alternative structures, a process called ‘tautomerisation’ thought to involve quantum tunnelling. In 1999, the physicist Jim Al-Khalili and I suggested that proton tunnelling might account for one very peculiar kind of mutation – so-called adaptive mutation – which appears to occur more frequently when it provides an advantage. Our paper was entirely theoretical, but we are currently attempting to find experimental evidence for proton tunnelling in DNA. So, watch this space.

Beneath all these quantum solutions to puzzling vital phenomena, we find ourselves with a deeper mystery. Quantum coherence is an immensely delicate phenomenon, depending on those in-tune particle waves. To maintain it, physicists usually have to enclose their systems within near-perfect vacuums and cool them down to very close to absolute zero temperature to freeze out any heat-driven molecular motion. Molecular vibrations are the mortal enemy of quantum coherence. How, then, does life manage to maintain its molecular order for long enough to perform its quantum tricks in warm and wet cells? That remains a profound riddle. Recent research offers a tantalising hint that, instead of avoiding molecular storms, life embraces them, rather like the captain of a ship who harnesses turbulent gusts and squalls to maintain his ship upright and on-course. As Schrödinger predicted, life navigates a narrow stream between the classical and quantum worlds: the quantum edge.



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[Stormer0628]

It was such a dangerous finding that a pair of scientists had second thoughts announcing their discovery to the public.

The explosive event? The duo showed that two tiny particles known as bottom quarks could theoretically fuse together in a powerful flash. The result: a larger subatomic particle, a second, spare particle known as a nucleon, and a whole mess of energy spilling out into the universe. This "quarksplosion" would be an even more powerful subatomic analog of the individual nuclear fusion reactions that take place in the cores of hydrogen bombs—about eight to ten times more powerful in fact.

Quarks are tiny particles that are usually found clinging together to make up the neutrons and protons inside atoms. They come in six versions or "flavors": up, down, top, bottom, strange and charm.

Energetic events at the subatomic level are measured in megaelectronvolts (MeV), and when two bottom quarks fuse, the physicists found, they produce a whopping 138 MeV. That's about eight times more powerful than one of the individual nuclear fusion events that takes place in hydrogen bombs (a full-scale bomb blast consists of billions of these events). H-bombs fuse together tiny hydrogen nuclei known as deuterons and tritons to create helium nuclei, along with the most powerful explosions in the human arsenal. But each of those individual reactions inside the bombs releases only about 18 MeV, according to the Nuclear Weapon Archive, a website devoted to collecting research and data about nuclear weapons. That’s far less than the fusing bottom quarks’ 138 MeV. [Beyond Higgs: 5 Elusive Particles That May Lurk in the Universe]

"I must admit that when I first realized that such a reaction was possible, I was scared," co-researcher Marek Karliner of Tel Aviv University in Israel told Live Science. "But, luckily, it is a one-trick pony."

As powerful as fusion reactions are, a single instance of fusion on its own isn't at all dangerous. Hydrogen bombs derive their enormous power from chain reactions — the cascading fusion of lots and lots of nuclei all at once.

Karliner and Jonathan Rosner, of the University of Chicago, determined that such a chain reaction wouldn't be possible with bottom quarks, and, before publishing, privately shared their insight with colleagues, who agreed.

"If I thought for a microsecond that this had any military applications, I would not have published it," Karliner said.

To spark a chain reaction, nuclear bomb makers need large stockpiles of particles. And an important property of bottom quarks makes them impossible to stockpile: They wink out of existence just 1 picosecond after they're created, or in about the time it takes light to travel half the length of a single grain of salt. After that time span, they decay into a far more common and less energetic kind of subatomic particle, known as the up quark.

It might be possible to generate single fusion reactions of bottom quarks inside miles-long particle accelerators, the scientists said. But even inside an accelerator, one couldn't assemble a large enough mass of quarks to do any damage out in the world, the researchers said. So there’s no need to worry about bottom quark bombs. [7 Strange Facts About Quarks]

The discovery is exciting, though, because it's the first theoretical proof that it's possible to fuse subatomic particles together in ways that release energy, Karliner said. That's brand-new territory in the physics of very tiny particles, made possible by an experiment in the Large Hadron Collider at CERN, the massive particle-physics laboratory near Geneva.

Here's how the physicists made this discovery.

At CERN, particles zip around a 17-mile-long (27 kilometers) underground ring at near light speed before smashing into one another. The scientists then use powerful computers to sift through the data from those collisions, and strange particles sometimes emerge from that research. In June, something especially strange turned up in the data from one of those collisions: a "doubly charmed" baryon, or a bulky cousin of the neutron and proton, itself made up of two cousins of the "bottom" and "top" quarks known as "charm" quarks.

Now, charm quarks are very heavy compared to the more common up and down quarks that make up protons and neutrons. And when heavy particles bind together, they convert a large chunk of their mass into binding energy, and in some cases, produce a bunch of leftover energy that escapes into the universe. [Wacky Physics: The Coolest Little Particles in Nature]

When two charm quarks fuse, Karliner and Rosner found, the particles bind with an energy of about 130 MeV and spit out 12 MeV in leftover energy (about two-thirds of the energy of deuteron-triton fusion). That charmed fusion was the first reaction of particles on this scale ever found to emit energy in this way, and is the headline result of the new study, published yesterday (Nov. 1) in the journal Nature.

The even more energetic fusion of two bottom quarks, which bind with an energy of 280 MeV and spit out 138 MeV when they fuse, is the second, and more powerful of the two reactions discovered.



SOURCE

 

[Stormer0628]

Physicists aren’t often reprimanded for using risqué humour in their academic writings, but in 1991 that is exactly what happened to the cosmologist Andrei Linde at Stanford University. He had submitted a draft article entitled ‘Hard Art of the Universe Creation’ to the journal Nuclear Physics B. In it, he outlined the possibility of creating a universe in a laboratory: a whole new cosmos that might one day evolve its own stars, planets and intelligent life. Near the end, Linde made a seemingly flippant suggestion that our Universe itself might have been knocked together by an alien ‘physicist hacker’. The paper’s referees objected to this ‘dirty joke’; religious people might be offended that scientists were aiming to steal the feat of universe-making out of the hands of God, they worried. Linde changed the paper’s title and abstract but held firm over the line that our Universe could have been made by an alien scientist. ‘I am not so sure that this is just a joke,’ he told me.

Fast-forward a quarter of a century, and the notion of universe-making – or ‘cosmogenesis’ as I dub it – seems less comical than ever. I’ve travelled the world talking to physicists who take the concept seriously, and who have even sketched out rough blueprints for how humanity might one day achieve it. Linde’s referees might have been right to be concerned, but they were asking the wrong questions. The issue is not who might be offended by cosmogenesis, but what would happen if it were truly possible. How would we handle the theological implications? What moral responsibilities would come with fallible humans taking on the role of cosmic creators?

Theoretical physicists have grappled for years with related questions as part of their considerations of how our own Universe began. In the 1980s, the cosmologist Alex Vilenkin at Tufts University in Massachusetts came up with a mechanism through which the laws of quantum mechanics could have generated an inflating universe from a state in which there was no time, no space and no matter. There’s an established principle in quantum theory that pairs of particles can spontaneously, momentarily pop out of empty space. Vilenkin took this notion a step further, arguing that quantum rules could also enable a minuscule bubble of space itself to burst into being from nothing, with the impetus to then inflate to astronomical scales. Our cosmos could thus have been burped into being by the laws of physics alone. To Vilenkin, this result put an end to the question of what came before the Big Bang: nothing. Many cosmologists have made peace with the notion of a universe without a prime mover, divine or otherwise.

At the other end of the philosophical spectrum, I met with Don Page, a physicist and evangelical Christian at the University of Alberta in Canada, noted for his early collaboration with Stephen Hawking on the nature of black holes. To Page, the salient point is that God created the Universe ex nihilo – from absolutely nothing. The kind of cosmogenesis envisioned by Linde, in contrast, would require physicists to cook up their cosmos in a highly technical laboratory, using a far more powerful cousin of the Large Hadron Collider near Geneva. It would also require a seed particle called a ‘monopole’ (which is hypothesised to exist by some models of physics, but has yet to be found).

The idea goes that if we could impart enough energy to a monopole, it will start to inflate. Rather than growing in size within our Universe, the expanding monopole would bend spacetime within the accelerator to create a tiny wormhole tunnel leading to a separate region of space. From within our lab we would see only the mouth of the wormhole; it would appear to us as a mini black hole, so small as to be utterly harmless. But if we could travel into that wormhole, we would pass through a gateway into a rapidly expanding baby universe that we had created. (A video illustrating this process provides some further details.)

We have no reason to believe that even the most advanced physics hackers could conjure a cosmos from nothing at all, Page argues. Linde’s concept of cosmogenesis, audacious as it might be, is still fundamentally technological. Page, therefore, sees little threat to his faith. On this first issue, then, cosmogenesis would not necessarily upset existing theological views.

But flipping the problem around, I started to wonder: what are the implications of humans even considering the possibility of one day making a universe that could become inhabited by intelligent life? As I discuss in my book A Big Bang in a Little Room (2017), current theory suggests that, once we have created a new universe, we would have little ability to control its evolution or the potential suffering of any of its residents. Wouldn’t that make us irresponsible and reckless deities? I posed the question to Eduardo Guendelman, a physicist at Ben Gurion University in Israel, who was one of the architects of the cosmogenesis model back in the 1980s. Today, Guendelman is engaged in research that could bring baby-universe-making within practical grasp. I was surprised to find that the moral issues did not cause him any discomfort. Guendelman likens scientists pondering their responsibility over making a baby universe to parents deciding whether or not to have children, knowing they will inevitably introduce them to a life filled with pain as well as joy.

Other physicists are more wary. Nobuyuki Sakai of Yamaguchi University in Japan, one of the theorists who proposed that a monopole could serve as the seed for a baby universe, admitted that cosmogenesis is a thorny issue that we should ‘worry’ about as a society in the future. But he absolved himself of any ethical concerns today. Although he is performing the calculations that could allow cosmogenesis, he notes that it will be decades before such an experiment might feasibly be realised. Ethical concerns can wait.

Many of the physicists I approached were reluctant to wade into such potential philosophical quandaries. So I turned to a philosopher, Anders Sandberg at the University of Oxford, who contemplates the moral implications of creating artificial sentient life in computer simulations. He argues that the proliferation of intelligent life, regardless of form, can be taken as something that has inherent value. In that case, cosmogenesis might actually be a moral obligation.

Looking back on my numerous conversations with scientists and philosophers on these issues, I’ve concluded that the editors at Nuclear Physics B did a disservice both to physics and to theology. Their little act of censorship served only to stifle an important discussion. The real danger lies in fostering an air of hostility between the two sides, leaving scientists afraid to speak honestly about the religious and ethical consequences of their work out of concerns of professional reprisal or ridicule.

We will not be creating baby universes anytime soon, but scientists in all areas of research must feel able to freely articulate the implications of their work without concern for causing offence. Cosmogenesis is an extreme example that tests the principle. Parallel ethical issues are at stake in the more near-term prospects of creating artificial intelligence or developing new kinds of weapons, for instance. As Sandberg put it, although it is understandable that scientists shy away from philosophy, afraid of being thought weird for veering beyond their comfort zone, the unwanted result is that many of them keep quiet on things that really matter.

As I was leaving Linde’s office at Stanford, after we’d spent a day riffing on the nature of God, the cosmos and baby universes, he pointed at my notes and commented ruefully: ‘If you want to have my reputation destroyed, I guess you have enough material.’ This sentiment was echoed by a number of the scientists I had met, whether they identified as atheists, agnostics, religious or none of the above. The irony was that if they felt able to share their thoughts with each other as openly as they had with me, they would know that they weren’t alone among their colleagues in pondering some of the biggest questions of our being.


SOURCE

 

[Stormer0628]

The Nature of Space and Time
A pair of researchers have uncovered a potential bridge between general relativity and quantum mechanics — the two preeminent physics theories — and it could force physicists to rethink the very nature of space and time.

Albert Einstein’s theory of general relativity describes gravity as a geometric property of space and time. The more massive an object, the greater its distortion of spacetime, and that distortion is felt as gravity.

In the 1970s, physicists Stephen Hawking and Jacob Bekenstein noted a link between the surface area of black holes and their microscopic quantum structure, which determines their entropy. This marked the first realization that a connection existed between Einstein’s theory of general relativity and quantum mechanics.

Less than three decades later, theoretical physicist Juan Maldacena observed another link between between gravity and the quantum world. That connection led to the creation of a model that proposes that spacetime can be created or destroyed by changing the amount of entanglement between different surface regions of an object.

In other words, this implies that spacetime itself, at least as it is defined in models, is a product of the entanglement between objects.

To further explore this line of thinking, ChunJun Cao and Sean Carroll of the California Institute of Technology (CalTech) set out to see if they could actually derive the dynamical properties of gravity (as familiar from general relativity) using the framework in which spacetime arises out of quantum entanglement. Their research was recently published in arXiv.

Using an abstract mathematical concept called Hilbert space, Cao and Carroll were able to find similarities between the equations that govern quantum entanglement and Einstein’s equations of general relativity. This supports the idea that spacetime and gravity do emerge from entanglement.

Carroll told Futurism the next step in the research is to determine the accuracy of the assumptions they made for this study.

“One of the most obvious ones is to check whether the symmetries of relativity are recovered in this framework, in particular, the idea that the laws of physics don’t depend on how fast you are moving through space,” he said.

A Theory of Everything
Today, almost everything we know about the physical aspects of our universe can be explained by either general relativity or quantum mechanics. The former does a great job of explaining activity on very large scales, such as planets or galaxies, while the latter helps us understand the very small, such as atoms and sub-atomic particles.

However, the two theories are seemingly not compatible with one another. This has led physicists in pursuit of the elusive “theory of everything” — a single framework that would explain it all, including the nature of space and time.

Because gravity and spacetime are an important part of “everything,” Carroll said he believes the research he and Cao performed could advance the pursuit of a theory that reconciles general relativity and quantum mechanics. Still, he noted that the duo’s paper is speculative and limited in scope.

“Our research doesn’t say much, as yet, about the other forces of nature, so we’re still quite far from fitting ‘everything’ together,” he told Futurism.

Still, if we could find such a theory, it could help us answer some of the biggest questions facing scientists today. We may be able to finally understand the true nature of dark matter, dark energy, black holes, and other mysterious cosmic objects.

Already, researchers are tapping into the ability of the quantum world to radically improve our computing systems, and a theory of everything could potentially speed up the process by revealing new insights into the still largely confusing realm.

While theoretical physicists’ progress in pursuit of a theory of everything has been “spotty,” according to Carroll, each new bit of research — speculative or not — leads us one step closer to uncovering it and ushering in a whole new era in humanity’s understanding of the universe.




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[dukerodukero]

Re: Making Universe Out of Nothing At All

Hi Stormer....Found answers to my questions here....Thank You Very Much...Now i can Sleep

 

[Stormer0628]

Re: Making Universe Out of Nothing At All

Hi Stormer....Found answers to my questions here....Thank You Very Much...Now i can Sleep

Glad to be of help. Hardly have time these days but will update at first chance.