How can experiments be done to confirm such sizes? Do we have a way to check all these tiny times and all these huge energies? The answer is yes, it can be tested and the experiment whose results were published a month ago is another one of these tests
"During the month of March 2014, we received the first experimental confirmation that the universe underwent an accelerated expansion a fraction of a second after the Big Bang and further confirmation of Einstein's theory of general relativity. This is how we expand our understanding of reality and take another step closer to a theory of everything and to a complete understanding of our universe and how it was created. Welcome to the third part of a brief history of the universe! In this series we will review both the insights we have been able to reach to date in the field of cosmology
- Genesis was empty - how was our universe created? - Part a'
- Genesis was empty - how was our universe created? - Part II'
- Genesis was empty - how was our universe created? - Part III
- Genesis was empty - how was our universe created? - Part IV
Experimental confirmations
How can experiments be done to confirm such sizes? Do we have a way to check all these tiny times and all these huge energies? The answer is yes, you can check it andThe experiment whose results were published about a month ago is another one of these tests. To date there have been five groundbreaking experiments in the field of cosmology (the study of the entire universe) by astronomical observations, but we are also testing these theories with the help of particle accelerators. The discovery of the Higgs particle last year was made at the largest particle accelerator in Switzerland (known as the LHC). In an accelerator they cause protons to collide and thus cause an explosion with enormous energy.
The energy released from the explosion is in turn rolled into particles with large masses. To discover the Higgs particle they created a collision that had a temperature of about 140,000,000,000,000 (140 thousand trillion) degrees Celsius. Note that these are the temperatures that prevailed in the early universe when it existed for less than one second when the last two forces separated from the unified force, the weak nuclear force and the electromagnetic force. Therefore, immediately after the discovery of the Higgs particle, the scientists claimed that they were able to restore in an accelerator energy that was at the dawn of the universe, immediately after the big bang. This experiment confirmed our theory that explains the connection between the Higgs and the breaking of the electro-weak force into the electromagnetic force and the weak nuclear force as well as the connection between the Higgs and the creation of the mass of the elementary particles in nature. Thus, with the help of one experiment, we were able to confirm both the standard model of the elementary particles that make us up and the standard model of cosmology and the idea of the unification of forces and the breaking of symmetry that happened immediately after the big bang.
We still don't know exactly how the forces unite into one force (and on the other hand how the unified force breaks into the four forces that exist today), but at least we know how the electromagnetic force and the weak nuclear force unite into one force on the way to the long-awaited unification of all forces as was probably immediately after the big Bang. We reached an impressive technological achievement when we managed to create in the particle accelerator the conditions and enormous energies that prevailed in the universe less than a second after the big bang. Thus we were able to confirm the electroweak force, but note that in order to further confirm the idea of the unification of forces we now need to build even stronger particle accelerators. In order to reach the next energies in line, the energies in which there is the union of the strong force with the electro-weak force, we need to build accelerators that will be able to create an enormous energy that is greater than the energy we were able to create at the moment in the LHC by a billion times!
A video translated by the Davidson Institute explaining how the large particle accelerator - LHC works - in which they confirmed the existence of the Higgs particle
Will we be able to build such large particle accelerators? How can we continue to test our theories about the Big Bang at such enormous energies and such distant times in the past? For this we must move to astronomical observations of the universe itself. As I noted, to date there have been five ground-breaking experiments in the field of cosmology (the study of the entire universe) by astronomical observations. The fifth and final experiment is the experiment whose results have now been reported. The greatness of this experiment is that by astronomical observation the experiment team was able to skip the energy gap and show what happened at times corresponding to that enormous energy that prevailed during the breaking of the strong nuclear force from the unified force. But we are ahead of the later. The first experiment that started the field of cosmology were the observations made by the British astronomer Edwin Hubble in the XNUMXs. He tried to show that there are other galaxies besides our Milky Way galaxy. Light traveling millions of light-years away from distant galaxies traveled through empty space undisturbed until it reached his telescope. Not only did Hubble discover that there are many galaxies beyond our own, but it also saw that all of these galaxies are moving away from us. No matter which direction you look in the sky, all the galaxies seem to be moving away from us. How can it be that everyone is moving away from us? Are we that threatening?
If we recall the example of the inflatable balloon, the answer will become clear immediately. As the balloon is inflated, the galaxies drawn on it move away from each other. Any galaxy you look around you will see how the galaxies on all sides of it are moving away from it. The same is true in our case, when we look at the other galaxies they seem to be moving away from us. Our galaxy has no special importance, the same phenomenon will be measured in every galaxy. Actually the galaxies do not move at all, the one that expands is the space itself and the galaxies expand with it (just like in a balloon where the rubber stretches and the drawings of the galaxies expand with it. But there is one difference from the balloon. In the universe we will not see this expansion within the sphere of the galaxy because the gravitational force of the stars in the galaxy is strong and resists expansion A more accurate example would be a balloon in which the rubber expands and with it the pictures of the galaxies, but the galaxies themselves do not expand). With the help of Hubble's measurements we discovered the expansion of the universe. If the universe is getting bigger and bigger then in the past it was smaller and in the even more distant past the universe was even smaller. This way you can move backwards in time until all the points in the universe are at one point, the entire space will converge to a small point. This is of course the moment of the big bang and as we mentioned the whole universe was then compressed into a singular point. From measuring the size of the universe today and the speed of its expansion, it is easy to calculate how long ago the size of the universe was the size of a point. This calculation comes out to about 13,800,000,000 (13.8 billion) years.
The expansion of the universe is not constant in time and the dark energy puzzle
The big bang stems from Einstein's theory of general relativity. But when Einstein actually started the field of cosmology in 1919, the expansion of the universe was still unknown. Einstein believed that the universe was supposed to be eternal, infinite and constant. Therefore, when he saw that from his equations it appears that the universe is not stable in time, he added another term to the equation. A constant that should keep the universe static and constant. This term is called the cosmological constant. After the discovery of Hubble, Einstein removed the cosmological constant and claimed that "this is the biggest mistake of my life". Today it turns out that this organ was probably not a mistake after all. About a decade ago, accurate measurements of distant stars revealed that not only is the universe expanding and going at a constant speed (as Hubble measured), but that the expansion speed of space-time is accelerating! In other words, the galaxies seem to be moving away from us at an increasing speed. Since the days of Newton we know that for there to be acceleration a force must act. A ball, for example, will not move until it is kicked. The kick is the force that causes the ball to accelerate. The ball increases its speed and starts to move. If the expansion of the universe is accelerating there must be some force causing it to accelerate. But what power can do this? The only force we know of that can affect such a large scale of the universe is gravity. But gravity pulls stars towards each other, an action that is the opposite of expansion! What is going on here? What force causes the universe to expand at an increasing rate?
We still have no idea. But we have already invented for this strange phenomenon there! dark energy. There is some kind of energy that we don't know yet that causes our spacetime to accelerate its expansion. The dark energy puzzle is one of the most important questions that exist today. What does Einstein's cosmological constant have to do with it, you ask? Its constant was supposed to oppose the attraction in the universe between all the stars so that the universe would not collapse in on itself and thus the universe would be kept in a constant and stable state. Although the universe is unstable, it is now understood that the cosmological constant can explain the accelerated expansion of the universe. A kind of cosmological repulsive force so great that it creates accelerated expansion. We still have no idea what that cosmological constant is, but it turns out that when you're a genius even your mistakes are probably right..
The first experiment that confirmed that there was indeed a big bang came only in the sixties, after Albert Einstein had already passed away. Two engineers, Robert Wilson and Arno Panzias, actually experimented with communication on behalf of the Bell company. They knew nothing about the Big Bang Theory. But during the experiments when they pointed their antennas up they picked up background noise at a constant frequency. No matter which direction they tried to measure the sky there was always the same background noise at the exact same frequency, a frequency of 160.2 gigahertz. This is a micro frequency, like the waves of the microwave device in the kitchen, and it is suitable for a very low temperature of -270 degrees Celsius, which is 2.7 degrees above absolute zero (in the microwave device, the waves move from side to side, moving the water molecules in the food from side to side as well, thus causing the water to be heated). They accidentally discovered the cosmic background radiation. These are light waves (at a low frequency that we cannot see) and are leftovers from the big bang.
Author's note:
This coming June, Nir Lahav plans to give lectures on this topic as part of the series I give at cinemateks across the country, the science and reality research series (in the month of April, the lecture will be at the end of Holocaust Day on the topic: Is man's nature evil from his youth?) Please follow the blog posts free and happy.
More of the topic in Hayadan:
- First direct evidence of the existence of gravitational waves that caused the universe to swell immediately after the big bang - an interview with Prof. Avi Leib from Harvard University, the head of the department of the main researcher who performed the experiment
- We received an important message from the fraction of a second after the Big Bang - an interview with Prof. Mark Kamionkowski who devised the experiment
- How does the telescope at the South Pole that discovered the gravitational waves created by the Big Bang work?
- What are gravitational waves?
- An attentive ear to the echoes of the Big Bang
32 תגובות
The universe has no center, and there is no point where the big bang "happened". The Big Bang is the time when space unfolded from a space centered at a point (0 spatial dimensions) to a metric space where there is a distance between every two points.
The universe has no center, and there is no point where the big bang "happened". The Big Bang is the time when space unfolded from a space centered at a point (0 spatial dimensions) to a metric space where there is a distance between every two points.
oak
If the universe was rotating then it would have an axis of rotation. Stars on the axis would not move away, and stars perpendicular to the axis would move away faster than other stars.
It's not what you see.
I am neither a physicist nor a scientist of any kind, but I have a question in simple language,
Accelerating the distance of the galaxies is defined in the article as a phenomenon that has no explanation because the force of gravity is supposed to pull and not push, why is the following theory not proposed:
If we assume that the universe not only expands but also rotates around the point where the big bang happened, then on a large scale we have a centrifugal force that causes the galaxies to move away from the center while circling it, at the same time the gravitational force between the galaxies and themselves weakens because they also move away from each other,
So a constant centrifugal force and a gravitational force that is supposed to balance it but is getting weaker cause the movement to accelerate outwards.
In addition,
If we assume that the big bang not only dispersed matter but also compressed the remaining matter at the center of the explosion point,
So as you move away from the center, the force of gravity towards the center weakens and this also contributes to the acceleration of the outward movement.
I would be happy to receive a correction if I am fundamentally wrong.
Joseph,
If you don't mind, could you go through my questions again?
You wrote that a particle is a particle that passes through the force (of gravity) is the graviton and you equated it to a photon. If so, why doesn't it do to mass what a photon does to electrons?
I could not understand why the existence of a graviton does not eliminate the curvature of space predicted by the theory of relativity. Is the claim that the graviton is responsible for the curvature of space?
The theory of relativity describes spatial warping, time dilation and frame dragging as a result of gravity (for example, all of the above). If we leave for a moment the curvature of space, how does gravitational entropy explain the last two?
Yossi, thanks for the explanation.
Good,
I saw that the answer to the question of how gravitons escape from a black hole is related to virtual particles which are allowed to reverse the laws of physics (pass the speed of light, for example) to the point of Eisenberg's uncertainty.
http://curious.astro.cornell.edu/question.php?number=264
Yossi, Zvi, Nissim, Point, Israel,
Thank you for your answer, and with your permission, a few more layman's questions (if there are already answers to these questions, replace the 'E' with 'A'
Point wrote that it is possible to say that the curvature of space is created as a result of the flow of gravitons (meaning that there is a curvature in space) and perhaps Yossi wrote that a particle is a particle that passes through the force (of gravity) is the graviton. It seems to me that the two explanations do not dream together, because Yossi's explanation shows that one mass acts directly on another mass through the gravitons and not through the curvature of space. I guess I'm wrong but I'd love to know what my mistake is.
Another question that arises in this context is related to a black hole. If, as Yossi wrote, the graviton can be equated to a photon, and a black hole does not allow unlucky photons, who got too close to it, to escape, why shouldn't something similar happen to gravitons? Why are they allowed to escape the black hole? Is it because the gravitons don't act on themselves?
Joseph,
The theory of relativity describes spatial curvature, time dilation, frame dragging as a result of gravity. If we leave for a moment the curvature of space, how does gravitational entropy explain the last two. In the gravitational entropy theory, does one of the parts of the squared radius derive computationally?
questionnaire
Comets, like any other body, perform an approximately conical orbit - hyperbola, parabola, ellipse, or circle. If you take a cone and cut it at some angle, you will get one of the paths I mentioned (this is the origin of the name, and not an explanation of the phenomenon of course).
As Tzvi corrected me, a circular path, and also the path of the parabola are private micrograms (mathematically - the eccentricity of the circle is the eccentricity of the parabola is 1 - while the ellipse has an eccentricity between 0 and 1, and the eccentricity of the hyperbola is greater than 1).
If we assume that the sun is fixed in its place (not exact) and look at the trajectory of a (relatively) light body, we will get that the body performs a conical orbit, the type of orbit and its equation depend on the speed of the body. The problem only assumes attraction, which is inversely proportional to the square of the distance.
Newton wrote about a thought experiment that nicely illustrates the issue. Imagine that a cannon is placed on top of a high mountain with its barrel pointing horizontally. Suppose the cannon can be fired at different speeds. There are two interesting speeds - we will call them A and B.
If the cannon fires at a speed lower than a, the projectile will hit the ground.
If the cannon fires at exactly a speed - the trajectory will be a circle. The bullet will then begin to circle the Earth. At this speed the centripetal force is exactly equal to the gravitational force.
If a cannon is fired between speed A and speed B, the bullet will enter an elliptical trajectory.
If we shoot exactly at speed b (called the "escape velocity") - the trajectory will be parabolic and the projectile will move away forever.
And if above speed b - the trajectory will be hyperbolic. As speed increases, the hyperbola will straighten more.
I don't understand why you're trying to complicate things 🙂 We don't put the planets on a scale, but we generally know how to measure their mass, using Newton's equations.
Thanks Shmulik and Zvi for the answers about the routes.
I'm interested in whether in gravity systems there is only attraction or both forces
(Attraction and repulsion are equal)? There are several behaviors that may indicate this:
1. Comets that do not collide with the sun for some reason?
2. The mechanism in an elliptical orbit of approaching/accelerating, moving away/decelerating?
3. The direction of rotation of the planets is the same as that of the sun, perhaps because of gravity
And the rejection from the sun catches them like a flyer (on both sides)?
4. No one to this day has put a planet on a scale, but deduced its mass
From other data, so maybe it is not accurate to use this data to explain his route?
I am convinced that there are other explanations for these phenomena, the question is whether they are the same phenomena
Can they be explained with an element of repulsive force alongside gravity?
And a final question: according to the theory of relativity, a body with mass wrinkles the fabric of time/space
And so a gravitational force is created around it, but what happens if you look from below and in the place of a coil
Do we see a small hill? Are we looking at rejection?
Thanks.
refers to the graviton issue. Here is a possible explanation in layman's format.
From the point of view of a sufficiently long time - gravity, like any force, transfers energy in fixed portions. A particle whose force is the graviton, just as a photon is the particle of the atomic force. The regular dish is the graviton.
This has no contradiction to the classical picture we apparently see. But Professor Verlind came along and claimed that gravity does not exist below a certain size, being the product of variable mass compressions in space. This is similar to a gas: the atoms by themselves do not press. The spatial compression difference creates a compressive diffusion that we interpret as force. This seemingly contradicts the attempt to see gravity as quantum since according to him it is a product that can only be seen at subatomic distances.
The next part can be understood within the framework of relativity+quantum theory or within the framework of gravitational entropy theory:
The mediation is with very high energies and with the understanding that an experiment involving gravitons can be observed in the present and this is the big bang on the one hand and black holes on the other.
In this very high energy experiment and in the 13.5 billion years that have passed since then, it is possible to see a graviton. In an experiment conducted in Antarctica, they were able to see gravitational waves - I am not aware if it is also gravitons.
Shmulik
Until a few years ago the graviton was mentioned as being related to the Higgs if I remember correctly. I've always wondered about its mechanism of action - if it originates in the sun and it reaches the earth, shouldn't it push it instead of pulling it? Go understand bosons.
Shmulik and Nisim,
The elliptical orbits of the planets around the Sun are a result of Newtonian gravity, circular orbits in the two-body problem are stable but are simply a special case of an elliptical orbit. By the way, if you take into account additional effects such as tidal forces, they tend to round orbits so that in a certain respect circular orbits are more stable than elliptical orbits according to Newtonian mechanics (given non-point bodies).
As for relativistic gravity, it actually predicts deviations from elliptical orbits, and in the approximation of relatively weak gravity (that is, distances much larger than the Schwarzschild radius) it predicts precession of the ellipse, that is, the ellipse rotates and creates a sort of rose-like orbit. In fact, the first success of general relativity was the precise quantitative explanation it gave for the long-known precession of the planet Mercury.
hello Yossi
You wrote that Eric Verlind's theory is relatively simple to understand. I would appreciate it if you would articulate the main points of the theory in "layman's language".
Thanks in advance and happy Monday.
Shmulik
I think not. I think even in this model, a circular orbit is unstable. The elliptic orbit results from the dependence of the force on one part of the square of the distance.
I have an amazing Feynman book, which includes his lecture on Newton's development. The book is called Feynman's Lost Lecture. Explains nicely 🙂
Miracles,
If the curvature of the sun's space is supposed to be spherical, does that mean that over time there should be a convergence to a circular orbit?
Hi Shmulik,
The graviton is supposed to be closely related to space-time, so that the two descriptions will be equivalent.
It can be said that the curvature of space-time was created as a result of a flux of gravitons.
At least that's how Baryon is, but the problem is that there is no real quantum theory of gravity. In my opinion, part of the problem stems from the fact that quantum mechanics assumes a space-time framework in which the events take place. While a theory of gravity would probably have to include the fabric of space-time as its product. This roughly means that a graviton does not distort space-time but creates it.
questionnaire
The reason for an elliptical orbit and not a circular one has nothing to do with relativity. The one who discovered that the orbits are elliptical is Kepler, and the one who gave the explanation is Newton. The explanation assumes that the sun's gravitational force is in the direction of the sun, and its magnitude depends inversely on the square of the distance.
A circular orbit is unstable - it requires that the direction of the planet's speed be exactly perpendicular to the line connecting the planet to the sun. Assume that the velocity component is not perpendicular. Let's assume that at a certain moment, the direction of the velocity causes it to approach the sun - as the planet approaches, its velocity increases due to conservation of angular momentum. The opposite is also true. If you calculate the orbit of the planet - you get an ellipse equation.
Thank you Nissim,
What will we do with the graviton? Israel, are you familiar with the subject or did you only intervene in the subjects of chuppah and sanctification statistics?
Something can explain why according to the theory of relativity a mass of
A star warps time/space and the planets around it move
In an elliptical orbit and not a circular one (as expected)?
Shmulik
The scattering is a result of the effect of the photon's electric field on the electron, and I think vice versa as well. There is really no "contact between them".
There is an explanation here – http://farside.ph.utexas.edu/teaching/em/lectures/node96.html
Miracles,
In Thompson the photon does not throw an electron away as if they were both billiard balls? In short, it would be correct to say that the photon transfers momentum to the electron (in Thompson for example). What does the graviton do?
Shmulik
I don't get it either...so just one comment/clarification. Describe the collision of a photon with an electron. Both have size 0, so they don't really collide. Maybe it's not so different from the curvature of space in general relativity?
Miracles, Israel, friends...
I have a stupid question and I would appreciate an answer: what exactly is the Graviton expected to do?
Einstein showed that gravity is not actually a force but a curvature of space as a result of mass. For example, Earth rotates in its orbit around the sun, because the sun curves the space around it.
The idea for a unified theory gave birth to the idea for quantum gravity, which states that just as the electromagnetic field has a particle that transfers the force - the photon - so does gravity: the graviton. But the photon behaves as expected (occasionally): when it gets stuck in an electron it throws it off or is swallowed by it and raises it up. How is the graviton supposed to work? Does the sun send gravitons to Earth? Doesn't its existence (which has yet to be discovered) make the idea of the curvature of space redundant?
As promised, dumb questions…
Friends,
I have a stupid question and I would appreciate an answer: what exactly is the Graviton expected to do?
Einstein showed that gravity is not actually a force but a curvature of space as a result of mass. For example, Earth rotates in its orbit around the sun, because the sun curves the space around it.
The idea for a unified theory gave birth to the idea for quantum gravity, which states that just as the electromagnetic field has a particle that transfers the force - the photon - so does gravity: the graviton. But the photon behaves as expected (occasionally): when it gets stuck in an electron it throws it off or is swallowed by it and raises it up. How is the graviton supposed to work? Does the sun send gravitons to Earth? Doesn't its existence (which has yet to be discovered) make the idea of the curvature of space redundant?
As promised, dumb questions…
All in all, really beautiful and good articles
Thanks for this series of articles. They are written in a clear and interesting way.
I wanted to qualify my response. Adhere to scientific correctness and say only what is true and not what I think is true.
The entropy gravity theory is still not really accepted by everyone.
Great efforts are being made to combine it with quantum mechanics and string theory in order to possibly derive the other forces from it.
Today the professor is considered a leader and only 4 years passed from the publication of the theory to the willingness of other scientists to listen to it.
He is taken very seriously.
There is no need for dark energy according to the theory and it is also fundamentally simple to understand. Of course, the mathematical derivation is difficult.
Read the Wikipedia entry that refers to Eric Verlind.
There is apparently no dark energy. We will be skeptical and say that according to the entropy theory of gravity.
Eric Verlind's theory is not from the fringe stream but is very quickly becoming the mainstream. It was published in 2010 and 4 years have passed.
His innovations in mathematics caused a formula and algebra to be named after him: the Worlind formula and algebra by Worlind - he is still alive. By the way, he has a twin brother, Herman Verlind, who is known as a professor in his own right. Interestingly, the most prestigious award in the Netherlands is called the Spinoza Award and is approximately 2.5 million euros.
There is an alternative theory for dark energy and it is entropic gravity.
http://en.wikipedia.org/wiki/Erik_Verlinde
Scientist Eric Verlind is the winner of the 2011 Spinoza Prize, a well-known professor from the first line in the world.
It seems to me that he manages to explain dark energy without dark energy.
Verlind's theory is also very popular in the circles of quantum mechanics and in the more specific circle of string theory.
So maybe do your homework and stop using the term dark energy.
Two comments. A. It is worth emphasizing that there is no connection between Einstein's cosmological constant whose "job" is to keep the universe static (which is also true for a Newtonian universe) - and the cosmological constant caused by dark energy (it cannot be said that Einstein was right after all). B. The cosmic background radiation is not at one frequency, it is distributed over a spectrum of frequencies with the peak intensity at 160 GHz.