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Scientists Are Rethinking the Very Nature of Space and Time

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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.

References: New Scientist, arXiv

Article was originally published on Futurism.

How Much Do You Know About Fourth-Dimension?

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Stephen Hawking Was Wrong: "Spacetime Was Infinite At The Big Bang"

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According to Einstein's theory of relativity, the curvature of space-time was infinite at the big bang. In fact, at this point all mathematical tools fail, and the theory breaks down. However, there remained the notion that perhaps the beginning of the universe could be treated in a simpler manner, and that the infinities of the big bang might be avoided. This has indeed been the hope expressed since the 1980s by the well-known cosmologists James Hartle and Stephen Hawking with their "no-boundary proposal", and by Alexander Vilenkin with his "tunneling proposal".

Now scientists at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute/AEI) in Potsdam and at the Perimeter Institute in Canada have been able to use better mathematical methods to show that these ideas cannot work. The big bang, in its complicated glory, retains all its mystery.

"Hence the "no-boundary proposal" does not imply a large universe like the one we live in, but rather tiny curved universes that would collapse immediately", says Jean-Luc Lehners, who leads the "theoretical cosmology" group at the AEI.

One of the principal goals of cosmology is to understand the beginning of our universe. Data from the Planck satellite mission shows that 13.8 billion years ago the universe consisted of a hot and dense soup of particles. Since then the universe has been expanding. This is the main tenet of the hot big bang theory, but the theory fails to describe the very first stages themselves, as the conditions were too extreme. Indeed, as we approach the big bang, the energy density and the curvature grow until we reach the point where they become infinite.

As an alternative, the "no-boundary" and "tunneling" proposals assume that the tiny early universe arose by quantum tunneling from nothing, and subsequently grew into the large universe that we see. The curvature of space-time would have been large, but finite in this beginning stage, and the geometry would have been smooth - without boundary (see Fig. 1, left panel). This initial configuration would replace the standard big bang. However, for a long time the true consequences of this hypothesis remained unclear.

Now, with the help of better mathematical methods, Jean-Luc Lehners, group leader at the AEI, and his colleagues Job Feldbrugge and Neil Turok at Perimeter Institute, managed to define the 35 year old theories in a precise manner for the first time, and to calculate their implications. The result of these investigations is that these alternatives to the big bang are no true alternatives.

As a result of Heisenberg's uncertainty relation, these models do not only imply that smooth universes can tunnel out of nothing, but also irregular universes. In fact, the more irregular and crumpled they are, the more likely (see Fig. 1, right panel).

Hence one cannot circumvent the big bang so easily. Lehners and his colleagues are now trying to figure out what mechanism could have kept those large quantum fluctuations in check under the most extreme circumstances, allowing our large universe to unfold.

More information: Job Feldbrugge et al. Lorentzian quantum cosmology, Physical Review D (2017). DOI: 10.1103/PhysRevD.95.103508

Scientists Detect An Entirely New Type Of Perturbation In Space-Time

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A signal detected from a galaxy located 130 million light-years away could provide new data on the origin of stars say experts, and it all has to do with Gravitational Waves, a cosmic phenomenon that until recently was thought to be only a theory.

Image: Cataclysmic collision. Dana Berry, SkyWorks Digital, Inc./Harvard-Smithsonian Center for Astrophysics

The phenomenon of gravitational waves was predicted by Albert Einstein in his theory of relativity. These waves are generated by the release of large amounts of energy, following the collision between objects of enormous density, such as black holes, providing relevant information about the origin of stars.

So far gravitational waves have been directly observed by scientists three times, the first on September 14, 2015, and in all cases, these were the result of collisions between black holes.

However, scientists at the American space observatory LIGO—Laser Interferometer Gravitational-Wave Observatory—and European VIRGO, a large interferometer designed to detect gravitational waves predicted by the general theory of relativity, believe they have witnessed a new source of gravitational disturbances, caused by the collision of two neutron stars, resulting from the collapse of supergiant stars.

Astronomer J. Craig Wheeler of the University of Texas at Austin launched speculation over a potential new LIGO detection by tweeting: “New LIGO. Source with optical counterpart. Blow your sox off,” reports New Scientist.

To corroborate the source of the cosmic waves, scientists pointed their telescopes, including Hubble, to a galaxy called NGC 4993 in order to gather more details.

Astronomers believe the signal has its origin in a binary neutron star belonging to that galaxy, located about 130 million light years from Earth.

While several astronomers have tweeted messages speculating about the imminent detection of gravitational waves, LIGO observatory spokesman David Shoemaker has merely confirmed that “A very exciting O2 Observing run is drawing to a close August 25. We look forward to posting a top-level update at that time.”

Andy Howell, an astronomer at Las Cumbres University, composed a tweet saying how “watching the astronomical observations roll in is better than any story any human has ever told”, but didn’t give any information about what specifically he had spotted.

According to statements from LIGO and VIRGO, we can expect a statement about the discovery any day now.

Interestingly, according to NATURE, Public records show that NASA’s Fermi Gamma-ray Space Telescope has spotted γ-rays emerging from the same region of the sky as the potential gravitational-wave source.

The latest we know from astronomers is resumed in an update posted by The LIGO–Virgo collaboration saying: “Some promising gravitational-wave candidates have been identified in data from both LIGO and Virgo during our preliminary analysis, and we have shared what we currently know with astronomical observing partners. We are working hard to assure that the candidates are valid gravitational-wave events, and it will require time to establish the level of confidence needed to bring any results to the scientific community and the greater public. We will let you know as soon we have information ready to share.”

Time Is NOT Real: Physicists Show EVERYTHING Happens At The Same Time

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TIME is not real – it is a human construct to help us differentiate between now and our perception of the past, an equally astonishing and baffling theory states.

The concept of time is simply an illusion made up of human memories, everything that has ever been and ever will be is happening RIGHT NOW.

That is the theory according to a group of esteemed physicists who aim to solve one of the universe’s mysteries.

Most people do not even consider the concept of time but there is nothing in the laws of physics to state that it should move in the forward direction that we know.

The laws of physics are symmetric ultimately meaning that time could have easily moved in a backward direction as it does forward.

Time is a human concept

Indeed some adherents to the ‘big crunch’ theory say time WILL run backwards when the universe stops expanding and starts contracting back in on itself.

This conundrum as to why we interpret time in a forward motion has led scientists to question why.

Inevitably, some have concluded that time is simply human construct.

Past, present and future are all 'now'.

They argue that there is a ‘block-universe’ where time and space are connected, otherwise known as spacetime.

The theory, which is backed up Einstein’s theory of relativity, states that space and time are part of a four dimensional structure where everything thing that has happened has its own co-ordinates in spacetime.

This would allow everything to be ‘real’ in the sense that the past, and even the future, are still there in spacetime – making everything equally important as the present.

Time is formed by memories, according to physicists / GETTY Images

Massachusetts Institute of Technology physicist Max Tegmark, told space.com: "We can portray our reality as either a three-dimensional place where stuff happens over time, or as a four-dimensional place where nothing happens [‘block universe’] — and if it really is the second picture, then change really is an illusion, because there's nothing that's changing; it's all just there — past, present, future.

“We have the illusion, at any given moment, that the past already happened and the future doesn't yet exist, and that things are changing.
But all I'm ever aware of is my brain state right now. The only reason I feel like I have a past is that my brain contains memories.”

Julian Barbour, a British physicist who has authored several books on the subject of time, describes everything as a series of “nows”.

Dr Barbour told physicist and author Adam Frank in the book ‘About Time: Cosmology and Culture at the Twilight of the Big Bang’: "As we live, we seem to move through a succession of Nows, and the question is, what are they?” He explains, adding to the spacetime theory where everything has its own place: "You can think of it as a landscape or country. Each point in this country is a Now and I call the country Platonia, because it is timeless and created by perfect mathematical rules."

He adds that what we perceive as the past is simply an illusion formed in our brain.

Dr Barbour: "The only evidence you have of last week is your memory. But memory comes from a stable structure of neurons in your brain now. The only evidence we have of the Earth's past is rocks and fossils. But these are just stable structures in the form of an arrangement of minerals we examine in the present. The point is, all we have are these records and you only have them in this Now."

The MATH Of Time Travel REVEALED: Scientists Says We CAN Travel In Time

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According to a new study, time travel is—mathematically speaking—possible. A researcher has concluded that space should NOT be divided into three dimensions—where time is separated. Instead, four dimensions need to be imagined simultaneously as a space-time continuum in which the different directions are connected.

While time travel has only been possible in popular movies and books, a scientist has found that in reality, there’s more to time travel than what we previously believed.

A researcher has created a new, revolutionary model that reveals—mathematically—time travel is in fact possible. While it seems to work mathematically, experts have yet to come up with the ‘right’ materials to create a working ‘time machine’.

The study was recently published in the IOPscience Journal Classical and Quantum Gravityand argues that mathematically speaking we can travel in time:

In this paper, we present geometry which has been designed to fit a layperson’s description of a ‘time machine’. It is a box which allows those within it to travel backwards and forwards through time and space, as interpreted by an external observer. Timelike observers travel within the interior of a ‘bubble’ of geometry which moves along a circular, acausal trajectory through spacetime. If certain timelike observers inside the bubble maintain a persistent acceleration, their worldlines will close.

Our analysis includes a description of the causal structure of our spacetime, as well as a discussion of its physicality. The inclusion of such a bubble in a spacetime will render the background spacetime non-orientable, generating additional consistency constraints for formulations of the initial value problem. The spacetime geometry is geodesically incomplete, contains naked singularities, and requires exotic matter. (Source)

Ben Tippett, a mathematics and physics instructor at the University of British Columbia’s Okanagan campus has revealed that time travel is at least mathematically possible.

“People think of time travel as something of fiction, and we tend to think it’s not possible because we don’t actually do it. But mathematically, it is possible,” revealed Tippett.

According to a newly published study, Tippet concludes that space should NOT be divided into three dimensions—where time is separated. Instead, Tippett says four dimensions need to be imagined simultaneously as a space-time continuum in which the different directions are connected. Time travel.

Based on Einstein’s theory—the researchers argues that the curvature of space-time is responsible for the curved orbits of the planets in the universe.

The researcher argues that if space-time was not ‘curved’ planets in the universe would travel in a straight line.

Imagine yourself standing next to a MASSIVE STAR. There, space-time geometry becomes curved making all straight trajectories of nearby cosmic bodies to bend, following a curved path around the star.

“The time direction of the space-time surface also shows curvature. There is evidence showing the closer to a black hole we get, time moves slower,” says Tippett. “My model of a time machine uses the curved space-time — to bend time into a circle for the passengers, not in a straight line. That circle takes us back in time.”

For the study, Tippett came up with a mathematical model called Traversable Acausal Retrograde Domain in Space-time or more charismatically called TARDIS. Tippett describes it as a bubble of space-time geometry which is able to carry contents back and forth through space. This ‘bubble’ moves through space-time at a speed greater than the speed of light times 8, which consequently allows it to move backward in time.

“Studying space-time is both fascinating and problematic. And it’s also a fun way to use math and physics,” says Tippett. “Experts in my field have been exploring the possibility of mathematical time machines since 1949. And my research presents a new method for doing it.

However, while the researcher says its mathematically possible to travel in time, he doubts that anyone will ever build a working time machine in the near future.

“HG Wells popularized the term ‘time machine’ and he left people with the thought that an explorer would need a ‘machine or special box’ to actually accomplish time travel,” Tippett says.
“While it is mathematically feasible, it is not yet possible to build a space-time machine because we need materials – which we call exotic matter – to bend space-time in these impossible ways, but they have yet to be discovered,” concluded Tippett.

Source: Traversable acausal retrograde domains in spacetime

Reference: UBC instructor uses math to investigate possibility of time travel

The Milky Way -- "Could Harbor A Spacetime Tunnel The Size Of The Galaxy Itself Hiding In Dark Matter"

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Astrophysicists from the International School for Advanced Studies (SISSA) in Trieste, Italy, speculated in a 2015 study that wormholes, predicted by Einstein in his theory of General Relativity as areas where space and time are bent to manipulate the distance, are possible, and could be hiding within dark matter inside the Milky Way. But, It would take a huge mass to produce the manipulation of spacetime, and no evidence of their existence has ever been found. Based on their theory, our galaxy could be a huge wormhole (or space-time tunnel) and, if that were true, it would be "stable and navigable."

"If we combine the map of the dark matter in the Milky Way with the most recent Big Bang model to explain the universe and we hypothesize the existence of space-time tunnels, what we get is that our galaxy could really contain one of these tunnels, and that the tunnel could even be the size of the galaxy itself. But there's more," explains Paolo Salucci, astrophysicist with SISSA and a dark matter expert. "We could even travel through this tunnel, since, based on our calculations, it could be navigable. Salucci is among the authors of the paper published in Annals of Physics.

Although space-time tunnels (or wormholes or Einstein-Rosen bridges) have only recently gained great popularity among the public thanks to Christopher Nolan's sci-fi film, they have been the focus of astrophysicists' attention for many years.

"Obviously we're not claiming that our galaxy is definitely a wormhole, but simply that, according to theoretical models, this hypothesis is a possibility." Can it ever be tested experimentally? "In principle, we could test it by comparing two galaxies -- our galaxy and another, very close one like, for example, the Magellanic Cloud, but we are still very far from any actual possibility of making such a comparison."

To reach their conclusions the astrophysicists combined the equations of general relativity with an extremely detailed map of the distribution of dark matter in the Milky Way: "the map was one we obtained in a study we carried out in 2013," explains Salucci. "Beyond the sci-fi hypothesis, our research is interesting because it proposes a more complex reflection on dark matter."

As Salucci points out, scientists have long tried to explain dark matter by hypothesizing the existence of a particular particle, the neutralino, which, however, has never been identified at CERN or observed in the universe. But alternative theories also exist that don't rely on the particle, "and perhaps it's time for scientists to take this issue 'seriously'," concludes Salucci. "Dark matter may be 'another dimension', perhaps even a major galactic transport system. In any case, we really need to start asking ourselves what it is."

"Our result is very important because it confirms the possible existence of wormholes. But there's more. We could even travel through this tunnel, since, based on our calculations, it could be navigable. Just like the one we've all seen in the film ‘Interstellar'."

Scientists had believed any wormholes which exist in the universe could simply be the size of a pin prick. However, the team of astrophysicists say the one in our galaxy could be big enough to fit a spaceship which could traverse the cosmos, as they would likely exist in other spiral galaxies.

"Obviously we're not claiming that our galaxy is definitely a wormhole, but simply that, according to theoretical models, this hypothesis is a possibility,” Salucci observed.

Via SISSA

"The Big Bang Was A Mirage From A Collapsing Higher-Dimensional Star"

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Big Bang was a mirage from collapsing higher-dimensional star, theorists propose. While the recent Planck results “prove that inflation is correct”, they leave open the question of how inflation happened. A new The study could help to show how inflation was triggered by the motion of the Universe through a higher-dimensional reality.

The event horizon of a black hole — the point of no return for anything that falls in — is a spherical surface. In a higher-dimensional universe, a black hole could have a three-dimensional event horizon, which could spawn a whole new universe as it forms.

It could be time to bid the Big Bang bye-bye. Cosmologists have speculated that the Universe formed from the debris ejected when a four-dimensional star collapsed into a black hole — a scenario that would help to explain why the cosmos seems to be so uniform in all directions.

The standard Big Bang model tells us that the Universe exploded out of an infinitely dense point, or singularity. But nobody knows what would have triggered this outburst: the known laws of physics cannot tell us what happened at that moment.

“For all physicists know, dragons could have come flying out of the singularity,” says Niayesh Afshordi, an astrophysicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.

It is also difficult to explain how a violent Big Bang would have left behind a Universe that has an almost completely uniform temperature, because there does not seem to have been enough time since the birth of the cosmos for it to have reached temperature equilibrium.

To most cosmologists, the most plausible explanation for that uniformity is that, soon after the beginning of time, some unknown form of energy made the young Universe inflate at a rate that was faster than the speed of light. That way, a small patch with roughly uniform temperature would have stretched into the vast cosmos we see today. But Afshordi notes that “the Big Bang was so chaotic, it’s not clear there would have been even a small homogenous patch for inflation to start working on”.

In a paper posted in the arXiv preprint server1, Afshordi and his colleagues turn their attention to a proposal made in 2000 by a team including Gia Dvali, a physicist now at the Ludwig Maximilians University in Munich, Germany. In that model, our three-dimensional (3D) Universe is a membrane, or brane, that floats through a ‘bulk universe’ that has four spatial dimensions.

Ashfordi's team realized that if the bulk universe contained its own four-dimensional (4D) stars, some of them could collapse, forming 4D black holes in the same way that massive stars in our Universe do: they explode as supernovae, violently ejecting their outer layers, while their inner layers collapse into a black hole.

In our Universe, a black hole is bounded by a spherical surface called an event horizon. Whereas in ordinary three-dimensional space it takes a two-dimensional object (a surface) to create a boundary inside a black hole, in the bulk universe the event horizon of a 4D black hole would be a 3D object — a shape called a hypersphere. When Afshordi’s team modelled the death of a 4D star, they found that the ejected material would form a 3D brane surrounding that 3D event horizon, and slowly expand.

The authors postulate that the 3D Universe we live in might be just such a brane — and that we detect the brane’s growth as cosmic expansion. “Astronomers measured that expansion and extrapolated back that the Universe must have begun with a Big Bang — but that is just a mirage,” says Afshordi.

The model also naturally explains our Universe’s uniformity. Because the 4D bulk universe could have existed for an infinitely long time in the past, there would have been ample opportunity for different parts of the 4D bulk to reach an equilibrium, which our 3D Universe would have inherited.

The picture has some problems, however. Earlier this year, the European Space Agency's Planck space observatory released data that mapped the slight temperature fluctuations in the cosmic microwave background — the relic radiation that carries imprints of the Universe’s early moments. The observed patterns matched predictions made by the standard Big Bang model and inflation, but the black-hole model deviates from Planck's observations by about 4%. Hoping to resolve the discrepancy, Afshordi says that his is now refining its model.

Despite the mismatch, Dvali praises the ingenious way in which the team threw out the Big Bang model. “The singularity is the most fundamental problem in cosmology and they have rewritten history so that we never encountered it,” he says. Whereas the Planck results “prove that inflation is correct”, they leave open the question of how inflation happened, Dvali adds. The study could help to show how inflation is triggered by the motion of the Universe through a higher-dimensional reality, he says.

Nature doi:10.1038/nature.2013.13743

Via Zeeya Merali/nature.com and The Perimeter Institute

Image credit: The Perimeter Institute

New Research Suggests That Time Runs Backwards Inside Black Holes

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A new research paper published in Physical Review Letters has brought forward a significant new understanding of general relativity laws, and has found some strange physics taking place inside black holes. Specifically, that the direction of time could be reversed within them. Several physical procedures are perfectly symmetric in time. Take a pendulum for instance. If someone shows you a video of a pendulum swinging, you cannot differentiate if the video is actually moving forward or backward.

But some processes are not symmetric at all. We can tell that a pendulum will ultimately slow because of friction and we know that it was triggered at some point, so we can give a temporal direction to physics. The directionality of time and our view of it was called the "Arrow of Time" by British astronomer Arthur Eddington, and it has been connected to the entropy of the cosmos.

Event horizons ascend from the mathematics of general relativity, but the simplest mathematical explanation of an event horizon leads to a paradox. Event horizons must contain all the history of the cosmos, from the Big Bang to its death. This generates numerous complications as it assumes that the universe must be deterministic and that past and future are inscribed on the "skin" of black holes. While this paradox doesn’t affect explanations and forecasts of the physics of black holes, it is evidently a limiting factor in correctly understanding how black holes work.

The new research tries to fill this important gap in black hole physics. The elementary notion of this paper is grounded on the holographic principle. According to the author of the paper the event horizon is essentially a holographic screen, a hypersurface with a precise entropy. You can have two kinds of holographic screens, past holographic screens and future holographic screens, liable on whether the entropy inside the surface is increasing or decreasing.

Study author Netta Engelhardt told Phys.org "Holographic screens are in a sense a local boundary to regions of strong gravitational fields. Future holographic screens correspond to gravitational fields which pull matter together... whereas past holographic screens correspond to regions which spread matter out..."

If this principle is applied to the cosmos as a whole, the entropy arrow is steady with the second law of thermodynamics. Entropy increases, time moves forward. But the use of the law onto black holes yields an interesting outcome. Within a black hole, entropy decreases (things become more structured) and thus thermodynamically time runs backward.

Although this is an exciting consequence, the paper is important because it verifies the first area law in general relativity and it might have solved a long-standing problem in black holes physics.

Here Are 10 Facts about Space and Time That Everyone Should Know About

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1) Time passes more slowly in the orbit around earth than on the surface of the earth. This means that returning astronauts from space arrive home slightly younger. 2) The universe has been expanding for 13.7 billion years. This produces a cosmic horizon in space, where the light has not reached earth yet from objects further away from 12 to 13 billion light-years.

3) The shortest moment in time is defined by the Planck time, which is 5.391 06(32) × 10−44 s. It is determined by the Planck’s constant, the gravitational constant and speed of light. 4) Matter determines how space-time curves. General Relativity explains how a spaceship travelling any speed slows down as it passes through a gravitational field, such as passing the planet Earth.

The simplest definition of space-time is “space-time is any mathematical model that combines space and time into a single interwoven continuum” Space-time is a difficult concept to understand. Below are the 10 must-known facts about space-time.

5. NASA’s Voyager 1 is at the edge of our solar system, it is at the distance of 19 billion kilometers away and it takes over 16 hours to send or receive a radio signal.

6. Time hasn’t always existed, the theory of relativity suggests before the Big bang, 13.74 billion years ago, time and space didn’t exist.

7. The fundamental description of the universe does not take into account Past, Present and Future. According to the special theory of relativity, there is no such thing as future or the past; everyone’s time frame is relevant to each other.

8. Atomic clocks are the most accurate clocks ever built. Some clock can measure a single vibration in a single atom of Mercury.

9. Time on Earth is actually slowing down. This is due to the tidal friction of Sun and the moon. So the day is lengthening by 1.7 milliseconds each century.

10. The Cosmic Microwave Background is the remnant of the hot Big Bang that fills the entire sky. Certain fluctuations in the temperature on Cosmic Microwave Background could give us clues about other universes.

Image Credit: X-ray: NASA/CXC/Wisconsin/D.Pooley & CfA/A.Zezas; Optical: NASA/ESA/CfA/A.Zezas; UV: NASA/JPL-Caltech/CfA/J.Huchra et al.; IR: NASA/JPL-Caltech/CfA.

Scientists Detect An Entirely New Type Of Perturbation In Space-Time

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Using the LIGO and VIRGO space observatories, experts are researching an event in a galaxy located 130 light years away from Earth, which according to experts, could be evidence of a completely new perturbation in space-time. A signal detected from a galaxy located 130 million light-years away could provide new data on the origin of stars say experts, and it all has to do with Gravitational Waves, a cosmic phenomenon that until recently was thought to be only a theory.

Cataclysmic collision. Dana Berry, SkyWorks Digital, Inc./Harvard-Smithsonian Center for Astrophysics

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So far gravitational waves have been directly observed by scientists three times, the first on September 14, 2015, and in all cases, these were the result of collisions between black holes.

Astronomer J. Craig Wheeler of the University of Texas at Austin launched speculation over a potential new LIGO detection by tweeting: “New LIGO. Source with optical counterpart. Blow your sox off,” reports New Scientist.

To corroborate the source of the cosmic waves, scientists pointed their telescopes, including Hubble, to a galaxy called NGC 4993 in order to gather more details.

Astronomers believe the signal has its origin in a binary neutron star belonging to that galaxy, located about 130 million light years from Earth.

Andy Howell, an astronomer at Las Cumbres University, composed a tweet saying how “watching the astronomical observations roll in is better than any story any human has ever told”, but didn’t give any information about what specifically he had spotted.

According to statements from LIGO and VIRGO, we can expect a statement about the discovery any day now.

The latest we know from astronomers is resumed in an update posted by The LIGO–Virgo collaboration saying: “Some promising gravitational-wave candidates have been identified in data from both LIGO and Virgo during our preliminary analysis, and we have shared what we currently know with astronomical observing partners. We are working hard to assure that the candidates are valid gravitational-wave events, and it will require time to establish the level of confidence needed to bring any results to the scientific community and the greater public. We will let you know as soon we have information ready to share.”

Stephen Hawking Was Wrong: "Spacetime Was Infinite At the Big Bang"

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According to Einstein's theory of relativity, the curvature of spacetime was infinite at the big bang. In fact, at this point all mathematical tools fail, and the theory breaks down.

However, there remained the notion that perhaps the beginning of the universe could be treated in a simpler manner, and that the infinities of the big bang might be avoided. This has indeed been the hope expressed since the 1980s by the well-known cosmologists James Hartle and Stephen Hawking with their "no-boundary proposal", and by Alexander Vilenkin with his "tunnelling proposal".

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"Hence the "no-boundary proposal" does not imply a large universe like the one we live in, but rather tiny curved universes that would collapse immediately", says Jean-Luc Lehners, who leads the "theoretical cosmology" group at the AEI.

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As an alternative, the "no-boundary" and "tunneling" proposals assume that the tiny early universe arose by quantum tunnelling from nothing, and subsequently grew into the large universe that we see. The curvature of spacetime would have been large, but finite in this beginning stage, and the geometry would have been smooth - without boundary (see Fig. 1, left panel). This initial configuration would replace the standard big bang. However, for a long time the true consequences of this hypothesis remained unclear.