Why is it that when space time expands, the speed can be faster than the speed of light?

Because the speed at which space-time expands is not constrained by the theory of relativity. Who is the greatest physicist in human history? It is believed that it is none other than the famous scientist Albert Einstein in the last century.

He not only made extraordinary contributions to the field of physics: he proposed two major theories of relativity, which toppled down and rebuilt the entire physics edifice;

It has also played an indelible role in the human process. It is precisely because of the "mass energy equation" constructed by Einstein that the United States was able to successfully manufacture a nuclear bomb and end World War II. In his theory, the speed of light is the upper speed of the universe.

What is the speed of light? The speed of travel of 300,000 kilometers per second is also the upper limit of the speed of any matter in the universe under the condition of a single space. Moreover, it is impossible for an object with mass to reach the speed of light; Only photons, energy bodies, travel in a vacuum;

to fully reach the "speed of light". The invariance of the speed of light, together with the iron law that "the speed of light is insurmountable", constitute Einstein's system of special relativity. At the same time, it is the special theory of relativity that has brought human physics to a new level.

To this day, we still haven't overturned it.

However, many friends may know, is the speed of light really the fastest speed? Not necessarily. The expansion rate of the universe is already greater than the speed of light.

That's right, and according to NASA's judgment in the last century, the speed of space-time expansion is likely to exceed the speed of light by about ten times.

However, we need to pay attention to the following: Where does space-time expansion come from? 13 billion years ago, the cosmic great**. Time and space are expanding, and the universe is constantly changing; This is no longer speed in a purely physical sense.

The speed of light determines the relationship between time and space in the three-dimensional space in which we live. But space-time itself is not bound by the laws of physics. Although this may sound a bit tongue-twisting, we should be able to understand the meaning behind it if we think about it carefully.

Perhaps, "space-time expansion" is the key to our unveiling of the development of light-speed spacecraft.

This is a bit like a boat sailing in downwind water, where the final speed of the boat is the speed of the boat plus the speed of the current. In the process of propagation, light is accompanied by the expansion of the universe, and its propagation speed will be faster, because the speed of the expansion of the universe is also counted.

Because the speed of space-time expansion is not constrained by the theory of relativity, the idea that an object cannot exceed the speed of light is only assumed that its speed in stationary space cannot exceed the speed of light. But the universe is expanding, and space, one of the criteria used to measure speed, is itself changing.

Because when space-time expands, the speed in space will increase, and if the expansion speed is fast enough, it can exceed the speed of light.

According to the research, they believe that the current universe is still in a period of rapid expansion, and the speed of expansion of the universe at this stage has even exceeded the speed of light, which means that if we observe the distant edge of the universe through the radio slow shadow mirror, we are actually observing the edge of the universe very far ago, and according to scientists, the diameter of the universe is about 93 billion light years. But this edge is obvious, and it is not his real quality, because the universe is still in a period of rapid expansion, so when we capture these signals, the universe may not know how far it has expanded. Then we return to the question, why does the speed of light, which is the fastest speed in the universe, not exceed the speed of the expansion of the universe?

To answer this question, we must first understand how light is generated, knowing that before that, the whole universe, or this singularity, was in a state of chaos. At this time, the whole world was nothing, nothing was produced, and it was precisely because of the collision that occurred after the universe was great that there were all kinds of matter. It is based on such conditions that the light rays we now know are produced, as a kind of substance produced after the universe is large, in essence, it is actually the laws of the universe that must be followed, and the universe's definition of it, its upper line is the speed of light.

However, this law does not have a limit on the expansion rate formed in the later stage of the universe, because the early formulator of this condition is the universe itself. And in a sense, the expansion speed of the universe and the speed of light are not actually in the same dimension. It is not that the speed of expansion must be limited by the ultimate speed of the speed of light, the reason why we think that the expansion of the universe is slower than the speed of light is reasonable, mainly because the expansion we see in reality is very slow, and the heat generated by the universe ** causes its expansion to form a phenomenon, which is completely different from what we see in our daily life.

The speed of light travels at a speed of 300,000 kilometers in a vacuum, and the surrounding space of a massive object or black hole will turn the surrounding space into a distorted state.

Because the speed at which the universe expands is the result of calculations in five dimensions. Our universe is equivalent to a large ball that is constantly expanding in the four-dimensional space, and its expansion direction is not in the four-dimensional space, but in the five-dimensional space. The direction of light is not the same as the direction of the expansion of the universe.

If you have to take three-dimensional space as an example, you can find an inflated balloon to demonstrate, the direction of the expansion of the universe can be understood as the diameter of the balloon, and the direction of light can be understood as the surface of the balloon. When the balloon is inflated, the diameter expands by one centimeter, and the surface of the balloon must expand by more than one centimeter. If you inflate the balloon at an accelerated rate, then the expansion acceleration of the balloon's diameter will be multiplied by the acceleration of the expansion of the balloon's surface.

The speed of the expansion of the universe is greater than the speed of light, and you can understand that the act of inflation is not controlled by the surface of the balloon, but is the result of the accumulation of gas inside, so the expansion speed of the universe is actually not limited by the speed of light. Just like a balloon, the more gas inside, the faster it expands, so the expansion rate of the universe is constantly accelerating, which is the result of the accumulation of some kind of energy (possibly dark matter, dark energy), which has nothing to do with the speed of light.

There is no strict derivation of this aspect, only simple logic to prove it: if the universe expands slower than the speed of light, then every beam of light in the universe will end up on a certain planet, and there are countless rays of light in the universe, so every planet in the universe will be infinitely heated. Since this did not happen, we speculate that the universe should expand faster than the speed of light.

The expansion of the universe is directly manifested as an increase in space, so it is not limited by the speed of light.

However, since gravity has a certain degree of negative energy, the expansion of the universe will ideally always be gradually slowed down by gravity, and it is precisely to avoid this situation that Einstein conceived a cosmological constant to counteract this slowdown, but he regretted this subjective assumption in his later years.

However, according to the observation of celestial bodies in recent years, many studies have pointed out that the cosmic constant has the possibility of a real existence.

The universe is expanding faster than the speed of light? Scientist: There is another type of speed in the universe that is faster.

The published theory is that the universe expands faster and that light can never reach the boundaries of the universe.

Does a galaxy move faster than the speed of light, doesn't it mean that objects can't move faster than the speed of light? From our point of view, we and any point in space are expanding, and galaxies that are farther away from us, seem to move away from us at a faster rate. Even if the expansion rate is small, if multiplied by a large enough distance, the speed of objects far away from us will exceed the speed of light, which is far greater than we can imagine.

Such a situation does not contradict the theory of relativity, the speed of motion of an object cannot exceed the speed of light, it only applies to the movement of an object in space, it cannot constrain the expansion rate of space. In fact, the galaxy itself moves at a speed of only a few hundred or thousands of km/s, much less than the speed of light. The movement of galaxies is only a superficial phenomenon, and the expansion of the universe is the root cause.

The skyrocketing hypothesis holds that the universe experienced faster-than-light skyrockets in the very early days.

Starts at 10 36 seconds after the big ** and lasts between 10 33 and 10 32. Driven by the vacuum energy of negative pressure, the universe expanded by at least 10 78 during this period, well above the speed of light.

In addition, the speed at which the universe expands is not fixed relative to the Earth, and the latest correction of the Hubble constant is that the speed of the universe expanding is about 68 kilometers per second per million parsecs (3.26 million light-years).

Because the expansion of the universe is the expansion of the whole space, just like blowing up a balloon, if the earth is a point on the balloon, then the other points must be closer to each other in the process of blowing up the balloon, the slower the speed of moving away, and the farther away, the faster the speed of moving away.

According to the Hubble constant, if you are 3.26 million light-years away from the Earth, the speed of the universe is 68 kilometers per second because of the expansion of the universe, then if you are 3260 light-years away from the Earth (10 million parsecs), the speed of the universe is 680 kilometers per second.

By analogy, you'll find that 14.3 billion light-years away from Earth, the universe will expand and move away from Earth at the speed of light – which is exactly the time it takes for the light from the birth of the universe to reach Earth.

Since the speed of light is the limit of the speed of the universe, why is the expansion rate of the universe greater than the speed of light?

The average rate of expansion of the universe is about times the speed of light.

The theory of relativity tells us that mass can be converted into energy, and vice versa, when the speed of the object accelerates, the energy it has will continue to increase, and the ** of energy is the work done by the force that drives the object to accelerate, and with the continuous increase of energy, the mass of the object itself will continue to increase, which causes the acceleration of the object to be maintained, it is necessary to continuously increase the driving force, when the speed reaches a certain limit value, the force to maintain the acceleration becomes infinite, that is, It is no longer possible to continue to accelerate the object.

In the theory of relativity there is the following formula:

m＝m。Divide by [1-(u c) 2] under the root number

m。is the rest mass of the object, u is the speed of motion of the object, c is the speed of light (u c) 2 is the square in parentheses.

This formula shows that when the velocity of an object with a non-zero static mass is equal to the speed of light, the mass of the object becomes infinite, and in order for such an object to continue to accelerate at the speed of light, an infinite force is required to propel it, which is obviously impossible.

Therefore, it is impossible to have an object with a non-zero static mass with a velocity exceeding the speed of light. Only those particles with zero static mass can reach the speed of light, such as photons.

It's possible. The speed of the expansion of the universe is very slow, only 76 km s, but you must know that the expansion is the expansion of space!! The energy it produces is all the time.

The universe used to be the size of a leather ball, but the mass is the same as the now infinite universe (the density is unimaginable). The original four fundamental forces gravitational force electromagnetic force strong nuclear force weak nuclear force turned out to be one force: superforce.

The energy of the universe is so great that it can be seen how big it is to split one force into four forces.

Energy, force, and these forms of matter interact with each other at an unknown rate of many times faster than light (but they are not matter).

In fact, the expansion of the universe is extremely slow, but the collision of forces with each other as it expands is extremely fast!!

And the universe is a space, like the Milky Way among the many galaxies, which is 100,000 light-years away, enough to travel 100,000 years!!

A galaxy is so big, but what about the universe??? Space and time are meant to constrain matter, and matter alone cannot escape space no matter how fast it is, so there must be something in the universe that is faster than light!

Like a black hole, it sucks light into it with a strong gravitational pull, and although gravity cannot be regarded as speed, it is magnitude higher than light!

Everything is now based on Einstein's theory of relativity, including the idea that light is the fastest matter, and Einstein is also human!! Does the stuff in his head fit the universe??? There are also things he doesn't know.

The universe has what you want and what you can't think of!

The theory of relativity is mostly correct, I dare not doubt that. But n years ago, people thought that the speed of sound was the fastest, but now they can build airplanes that are faster than the speed of sound.

Now I think the speed of light is the fastest, and I will be able to find things faster than the speed of light in the future!

Maybe not in a few hundred years, not in a few thousand years, but someday a new theory of relativity will overturn all of that!!

I didn't educate children about not believing in relativity!!

The universe can of course expand beyond the speed of light. For example, during the explosion of the big **, within three minutes of the universe**, the universe expanded exponentially from the size of an atomic nucleus to several thousand light-years, until we have the size of the Milky Way today, that is, about 100,000 light-years. In addition, the fact that distant quasars can move away from us at close to the speed of light is not so fast on its own, but as a result of the expansion of the universe, because of the Hubble redshift, the regression speed is proportional to the distance, and four billion years ago we would have observed more quasars in the universe.

These quasars have long since moved away from our horizon at speeds faster than the speed of light and have never been observed again. It is worth mentioning that the expansion of space beyond the speed of light is not contradictory to the superluminal speed of matter in the theory of relativity. It can be said that the velocity of matter and the velocity of space are not in the same frame of reference, so in the early days of the great **, the expansion of space far exceeded the speed of particles, and you must know that the speed of particles was close to the speed of light at that time.