2021-06-09

Was Einstein wrong? New space-time theory shakes the throne of relativity

By yqqlm yqqlm

The American Fun Science website published on May 24 entitled”Is Einstein Wrong?” Why do some astrophysicists question the theory of space-time” article, the author is Colin Stewart. The full text is excerpted as follows:

At first, we thought that the earth is the center of the solar system. This idea has existed for more than 1,000 years. Then, Copernicus stood up and said that if we were just a planet orbiting the sun, the whole system would be much simpler. Although there were many objections at the beginning, as the newly invented telescope provided countless evidence, the ancient geocentric theory finally succumbed.

Next, Newton explained that gravity is the reason why planets orbit the sun. He said that all celestial bodies with mass have gravitational attraction between each other. According to him, we revolve around the sun because the sun pulls us, and the moon revolves around the earth because the earth pulls it. After Newton’s theory ruled for two and a half centuries, in 1915 Einstein proposed the general theory of relativity to replace it. This new theory cleverly explains the inconsistency in the orbit of Mercury, the solar eclipse observed on the coast of Africa in 1919 was confirmed in span>.

Einstein believed that gravity is the result of space bending, not caused by pulling. He said that all celestial bodies in the universe are in a smooth four-dimensional structure called”space-time”. Massive celestial bodies like the sun warp the space-time around it, so the earth’s orbit is ours The planet follows this curvature as a result. In our view, this is like Newtonian gravity.

Time and Space Theory has been on the throne for more than 100 years and has defeated all throne coveters so far. In 2015, it was discovered that Gravitational waves is a decisive victory. But like the previous doctrines, the space-time theory may also fall from the throne. This is because it is incompatible with the other giant in the Physics Zoo-quantum theory.

The quantum world is extremely weird. For example, a single particle can appear in two places at the same time. Only through observation can we force it to”choose one.” Before observation, we can only assign probabilities to possible outcomes.

In the 1930s, the Austrian physicist Erwin Schrödinger thought Come up with a way to reveal how abnormal this idea is. He imagined closing a cat in an airtight container with a vial of poison next to it, and a hammer above the bottle. The device connected to the hammer can measure particles. Quantum state. Whether the hammer smashes the medicine bottle and poisons the cat depends on the measurement result. According to quantum physics, Before this measurement was made, the particles were in two states at the same time, so the medicine bottle was broken and not broken, and the cat was alive and dead.

This concept cannot be reconciled with the smooth and continuous structure of time and space.”A gravitational field cannot appear in two places at the same time.” Theoretical physicist Sabina Hosenfeld said.

According to Einstein’s theory, space-time is warped by matter and energy; but quantum physics believes that matter and energy exist in multiple states at the same time, and they can be here and there.”So where is the gravitational field?” Hosenfeld said,”No one can answer this question, it’s a bit embarrassing.”

Combine general relativity with quantum theory? No way. Hosenfeld said:”If a certain amount of energy is exceeded, the probability obtained is greater than 1.” The maximum probability can only be 1, which means a certain result. Certainty is certain, and it cannot be more “certain” than “certain”.

Similarly, the answer sometimes given by calculation is infinity, then there is no Actual physics meaning. Therefore, the two sets of theories are mathematically incompatible.

Physicists seek”marriage”

So, physicists seek to”marriage” rival factions to ensure peace. They are exploring”quantum gravity theory, which is like launching the ultimate mediation to let two competitors share the throne. This makes theorists turn to some strange possibility.

The most famous one is probably string theory, the idea is:electrons and quarks Subatomic particles are composed of small, vibrating strings. Just as the strings on an instrument can play different notes, people who believe in string theory believe that different combinations of strings will produce different particles. The appeal of string theory is that, at least in theory, it can reconcile general relativity and quantum physics.

However, to justify it like a juggling, the string must vibrate in 11 dimensions, which is 7 more dimensions than Einstein’s space-time structure. So far, there is no experimental evidence that these extra dimensions do exist.

“This is a very interesting math problem. As for whether it can describe the time and space we are in, we will know through experiments.”Said Yorma Loko from the University of Nottingham, UK.

To a certain extent, inspired by string theory, other physicists took a different approach and proposed loop quantum gravity theory. If they eliminate one of the central tenets of general relativity, that time space is a smooth, continuous structure, they can make the two theories peaceful. They proposed that space-time is composed of a series of intertwined circles, and its structure is very, very small. It’s a bit like a piece of cloth:it looks like a smooth fabric at first glance, but if you look closely, you can see that it is actually knitted stitch by stitch. You can also think of it as a photo on a computer screen:if you zoom in, you can see that it is actually made up of pixels.

The problem is that what a physicist in the theory of loop quantum gravity says is really small. These defects in time and space can only be seen on the Planck scale, and the Planck scale is Refers to about one-trillionth of one-trillionth of a meter. It is too small. There are more circles in 1 cubic centimeter than the number of cubic centimeters in the entire observable universe.

Loko said:”If the difference in time and space is only on the Planck scale, it will be difficult to have a particle accelerator to test it.” That would require a power ratioThe Large Hadron Collider at CERN is an atomic pulverizer that is 1,000 trillion times more powerful. How can such a small spatiotemporal defect be detected? The answer is to look at a large area of ​​space.

The light that reaches the earth from the farthest point in the universe has gone through billions of light-years of time and space. Although the impact of each space-time defect is small, the interaction with many defects along the way is likely to add up to an observable impact. For the past ten years, astronomers have been using light from distant gamma-ray bursts to find evidence to corroborate the circle Quantum Gravity Theory. These cosmic flashes are the result of massive stars collapsing at the end of life. There are some things that we cannot explain yet. Hosenfeld said:”Their spectrum is systematically distorted.” But no one knows whether this distortion occurs when the flash is transmitted to the earth, or whether it is related to the ray burst itself. There is no conclusion yet.

The”gravitationalization” of the quantum world

To make progress, we may not stop at declaring that space-time is not the smooth, continuous structure that Einstein said.

According to Einstein’s point of view, space-time is like a stage, whether there are actors or not, it is there; even if there are no stars or planets scattered everywhere, space-time still exists. However, the physicists Laurent Friedel, Robert Leigh, and Jorge Minic believe that this statement restricts our thinking. They believe that space-time does not exist independently of the celestial bodies in it. Space-time is defined by the way celestial bodies interact. In this way, space-time is an artifact of the quantum world itself, rather than something that needs to be combined with it. Minich said:”This may sound weird, but it is the way to solve the problem.”

The theory is called Modular space-time is attractive because it may help solve another long-term problem of locality in theoretical physics and the famous entanglement phenomenon in quantum physics. A physicist can create a situation where two particles are brought together and their quantum properties are connected, and then they are separated by a long distance but they are still connected. Changing the characteristics of one particle immediately changes the characteristics of another particle, just as the speed of information from one particle to another is faster than the speed of light, which directly violates the theory of relativity. Einstein was so troubled by this phenomenon that he called it the”long-distance weird effect.”

Modular space-time theory can accept such behavior by redefining”separation”. If space-time originated in the quantum world, then”close” in the quantum sense is more important than”close” in the physical sense. Minich said:”Different observers will have different views on locality, depending on the specific situation.” This is a bit like our relationship with others:we will feel close to relatives in the distance, but with The strangers living on the same street are far away.

Fredel, Leigh and Minic have been exploring this idea for the past five years and believe they are slowly making progress. Minich said:”We want to be conservative and take it step by step, but it is really fascinating and exciting.”

This is undoubtedly a novel method, which seems to be the quantum world.””Gravitation” instead of”quantizing” gravity like loop quantum gravity theory. However, like any scientific theory, it needs to be verified. Currently, the three are studying how to fit time into their model.

This may sound too esoteric, and only scholars should pay attention to it, but it may have a more profound impact on our daily lives.”We are in space and shuttle in time. If our understanding of time and space changes, it will not only affect our understanding of gravity, but also our understanding of quantum theory,” Hosenfeld said.”We All current devices are based on quantum theory. If we have a deeper understanding of the quantum structure of space-time, it will have an impact on future technology, perhaps not 50 or 100 years later, but 200 years later. .”

Source:Reference News Network