Research done with the Chandra space telescope and the ground-based SLOAN sky scanner has confirmed the knowledge about the expansion rate of the universe from seven billion years ago - the period when dark energy overcame gravity
The composite image in the top image is of the galaxy cluster Abell 85 (Abell 85), located 740 million light years from Earth. The purple emission is millions of degrees hot gas detected in X-field images by the Chandra Space Observatory, and the other colors show the galaxies as seen by the Sloan Sky Surveyor (SDSS).
This galaxy cluster is one of 86 observed by Chandra to track the rate at which dark energy has shaped the expansion of the universe over the past 7 billion years.
Clusters of galaxies are the largest collapsing objects in the universe and are therefore an ideal source for studying properties The dark energy, the concealing form of A force repelling gravity that drives andaccelerates the expansion of the universe.
The illustration in the bottom image shows snapshots from a simulation performed by Volker Sprengel, representing the growth of the cosmic structure when the universe was 0.9 billion years old, 3.2 billion and 13.7 billion (today). The simulation shows how the universe evolved from a state where it was smooth to one containing a variety of structures. The gas seen in these images, where the yellow areas are stars and the bright structures are galaxies and galaxy clusters. The growth of these structures was initially driven by gravity, but later competition began with the repulsive force of dark energy. (see also will exist on the computer).
Understanding the nature of dark energy is one of the biggest problems in science. Among the possibilities for its existence, scientists count the cosmic constant, equivalent to the energy of empty space, an adaptation of the theory of relativity to a large scale, or a more general physical field. To allow the scientists to determine which of the possibilities is correct, the scientists used Chandra to study the increase in mass of the galaxy clusters over the past seven billion years.
The results are remarkably consistent with those obtained in previous measurements of the expansion of the universe using distance measurements, which revealed that Einstein's theory of general relativity works as expected on a large scale. The cluster research work, combined with other studies, also provided the strongest evidence to date that dark energy is the cosmic constant Or "nothing weighs something".
For information on the NASA website
Yuval Ne'am: All our knowledge of physics covers 5% of the universe
54 תגובות
point:
All forces must be taken into account. That's why I talked about (unclassified) potential energy and not gravitational potential energy.
When talking about cosmological entropy, gravity must be taken into account. And it is not such a simple matter.
fresh:
You don't read what you are told.
What do you think "order" is?
The more order there is in physics, the more unconverted potential energy there is.
You must understand that the increase of entropy is actually not a law of nature but a mathematical law.
The increase in entropy is the result of a transition from low-probability states to high-probability states.
The attempt to define the accumulation of matter as an expression of order is more appropriate for the Pesach order than for the physical order.
Entropy is disorder, and the principle is that the disorder is only increasing, therefore the "primordial primordial soup" that was after the big bang is a much less orderly state and less complex than patterns of galaxies and solar systems, intelligent life, etc. Therefore, at least on the face of it, there is a certain contradiction here.
fresh:
On the contrary: it is consistent with this principle.
To understand this you need to understand what entropy is.
One of the ways to intuitively describe entropy is as the numerical answer to the question "to what extent it is possible to guess what the original state was based on the current state".
In the case before us - a smooth universe could only be obtained from an even smoother location while a universe with accumulations of matter could be obtained from more diverse histories.
The entropy rule works to convert potential energy into kinetic energy (heat is one of its manifestations) and radiant energy.
Regarding the simulation that shows how the universe evolved from a state where it was smooth to one containing a variety of structures, doesn't this contradict the principle of entropy?
It was at Princeton that Gadel brought Einstein a possible solution of the Einstein equations for a rotating universe, from which it appears that in this state time goes backwards.
lion:
It turns out that they could be wrong too.
To their credit, some of the data we have today was not in their hands.
For example the fact that the expansion is accelerating was not even known when Gribbin wrote his book.
Note that this is the reasoning I mentioned as the main reason.
Be that as it may, I think they could understand that this was not the case even from the data they had.
Rotation around an undefined axis is in my opinion an undefined thing.
I can imagine a situation where different star systems rotate around a different axis, but to me the expression "rotation around an undefined axis" has no meaning at all and among other things - if the axis is not defined - neither the direction in which the centrifugal force acts nor the strength of that force are defined.
Michael R.
Just as the universe does not have a center and from every point it seems as if we are in the center, so also the universe, if it rotates around itself, does not have a specific axis but it seems to rotate around all possible axes. I searched in books and found the source from which I probably remembered the idea.
John Gribbin: In Search of the Edge of Time, 1992 or in the Hebrew translation - in search of the edges of time, Crown, 1993.
It turns out that Gadel came up with the idea in 1949 as an explanation for the non-collapse of the universe (it seems strange to me because it was many years after the discovery of the expanding universe by Abel). And for our purposes - if Gadel claimed this and Gribin proposes the rotation of the universe as theoretically enabling time travel (a rotation is enough for some tens of billions of years), so who are we to reject the idea. See pages 215 to 218 in the Hebrew book.
lion:
I struggled to get to the computer for another minute because right after I left it last time I thought that the most crucial argument against the rotation idea had just been omitted from my previous response.
To move bodies in rotational motion, force is needed.
In star systems such as planetary systems and galaxies, gravity does this.
In the absence of another force, if the stars of the universe were in rotational motion, then their rotational motion could also be attributed only to gravity.
What's the problem with that?
The problem is that gravity (directed towards the center of gravity) will never accelerate the bodies in the direction away from the center of gravity.
The movement of a body under the influence of gravity always slows down as the distance from the center of gravity increases.
Friends:
I'm a little pressed for time until next week, but I'll try to answer briefly:
To the cool commenter:
Such a gas - whose impulse is so strong as to move entire galaxies, should have been felt in other ways as well. Among other things, the friction with it was supposed to stop the movement of the stars in the galaxies and cause them to collapse. This requires much less than moving to ranges of billions of light years (and without inflation it would also require the galaxies to move at a speed exceeding the speed of light to reach these distances)
Beyond that, as I have already mentioned on other occasions - gas has a different effect on buildings with different specific gravity and a different shape of surface area.
For the little brother:
Your words are nothing but defamation that requires a particularly wild imagination.
Where do you get all the things that were tested if not from your imagination?
I see one and only one common denominator for all the disqualified sections and it is the common denominator I said.
Since this theory attributes inappropriate behavior to you personally, you find it appropriate to invent conspiracies.
I don't understand you.
I have already seen that you also know how to treat articles and comments in a matter-of-fact way, but for some reason you hold back and usually avoid doing so and prefer to just try to fight with everyone.
Yehuda of course happily joins you even though he was never prevented from publishing his words (which, because they are wrong - are also not acceptable)
lion:
A rotation such as the one you describe requires the existence of an objective and non-relative space and the question of the existence of such a universe has not been decided. It can be argued that such an explanation of the expansion of the universe allows for a decision, but there are many problems with this explanation such as:
1. How did the galaxies move to such great distances?
2. How do the light rays rotate together with the universe?
3. How can the angular velocity be uniform?
4. With a radius like that of the universe, the stars that are far from the center (assuming a constant angular velocity) must move at speeds that far exceed the speed of light.
5. All of the above has so far only referred to two dimensions! What about the third dimension? After all, a rotation like the one you propose could only explain acceleration in the direction of moving away from the axis of rotation.
I suppose that more failures can be found in the explanation, but I think the above should be enough.
to the little brother
Well, with a good sign and good fortune the scientist decided to publish your comment anyway. I think at least in some things I agree with you. On the other hand, it's just a shame that you didn't insert an additional clause:-
10. Censorship of unacceptable scientific ideas.
Let's hope little brother that the day will come when my father will renew his days as before and we will not remember what censorship is.
And by the way, I came back about two hours ago from Tel Aviv University. There was a lecture there on the occasion of the opening of the year of astronomy 2009. An interesting lecture. One of the lecturers was Professor Hagi Netzer, who lectured on the Big Bang, mass and dark energy while making a comical comparison to Hanukkah. A fun lecture! After the lecture I asked him the question that interests me about dark mass = gas, and he said that what is important is whether the movement of the particles is significant. That is, he did not dismiss it outright. I would have been happy to continue talking with him, but I did not allow myself to take up the time of the others' questions.
Good night
Sabdarmish Yehuda
Arieh Yehuda.
You bring up again, sharpening a point I mentioned a few months ago about the folding effect, isn't it a rotation?
When he pointed out in one of the cool comments about the possibility of entropy (or more precisely, an internally structured collapse, rather than random!), it is possible that the same mass is the gravity that creates the folding = the effect that creates an internal rotation. In my opinion, we are actually watching the process itself from different and intersecting information angles.
Is this what Yehuda meant when he wrote: "to stress the galaxies"??..
Another effect noted in another article about a solar wind breakout can be related to "matter" or gas (why not helium, actually?). And not growing stars? =Lack of expansion, especially when it comes to astronomical dimensions.
In one of the comments today I saw someone who mentioned the "flexible universe"..and a bit with a smile too..maybe we too
In a kind of temporary/general cosmoenergetic reduction in the process being woven around us?
Naturally, it is difficult to focus the questions in the darkness of the revolving and complex (literally).
But it can be seen pictorially even if not "scientifically correct", until all aspects are connected together.
Michael R. I have a question to you.
Why is it that in all the discussions about the accelerated expansion of the universe and the dark mass, the option of the rotation of the universe around itself is not mentioned (and then it is possible that the accelerated expansion is a result, if only in part, of the rotation of the universe)?
Michael, the paragraph you sent about the expansion of the universe is interesting.
Michael, I think the claim (which Yehuda supports) that there is a bridging material in the universe that expands as a gas can explain dark energy. There is not enough evidence and knowledge about the intergalactic matter. Even today we frequently receive new information from research spacecraft that discover new things about matter in the solar system.
As of today, it is impossible to dismiss the claim of intergalactic matter expansion as a source of dark energy outright
Michael,
You are very wrong!, there is censorship here that is still looking for its excuse 🙂
I will give you a number of tested candidates:
1. Not for ultra-Orthodox/religious people.
2. Not for anarchists.
3. Not for those who comment too much.
4. No personal attacks.
5. No to unclear writing.
6. Not for the uncultured.
7. Not for the squeamish.
8. Not for those who lack the connection to the news.
9. Not for those who have a 'pen name'.
The problem is that somehow those who are not in harmony with my father are always in harmony with the criteria, and those who are in harmony with the site manager (or my father himself) - they are allowed.
So it seems jarring and so the search for 'criteria' is on.
But you demonstrate knowledge of what is happening on Yehuda's website and that is already a reason to smile.
Don't worry - the good guys will win.
The nursing brother
The cool commenter:
here. I found a link to a similar article:
http://arxiv.org/abs/hep-th/0410270
The cool commenter:
The article I spoke about in response 11 was published in the October November issue of Scientific American Israel.
I found a link to the table of contents of the issue but not to the article itself which was probably not uploaded to the website.
If you want to read it you will probably have to find a hard copy of the issue.
Yehuda:
That was clear.
It's just hard to believe you didn't get it.
By the way - there is no scientific censorship here.
In fact - apart from censorship in favor of cultural behavior I have never encountered any kind of censorship here.
The only comments that have ever been deleted are offensive comments about a person's body.
The fact that not everything you want to publish is ready to be published as an advertisement of the site (in the part that precedes the comments) cannot be called censorship. The website has the right to publish in its name what it thinks is right to publish. There are a great many articles of real science that are not published, so why do you complain?
That is, according to you Aryeh Seter, the intention was that the dark energy prevents the clusters of galaxies from increasing in their mass because the attraction of additional galaxies will be reset by the dark energy.
Sounds reasonable.
This of course does not make me a follower of dark energy but at least to understand what seemed to me to be a contradiction. So if I understood correctly, thank you Aryeh Seter.
Good night
Sabdarmish Yehuda
Yehuda, you wrote in one of your responses to this article "I also don't understand how dark energy prevents the expansion of galaxies when its entire theoretical function is actually to justify the accelerated expansion of the universe."
Let me explain to you and it's very simple.
In the article it is written that the dark energy prevents the galaxy clusters from growing further, i.e. from attracting more galaxies to them. As we know, galaxies tend to turn into clusters and clusters into megaclusters due to the mutual attraction between them. The dark energy works against this and thus prevents the clusters from growing - not from spreading.
The camel does not see its hump, and I live well with my habits. They are great.
And the scientific censorship? - is a problem of the censor and not of the censored,
And I will not change the way I write for any censor or "nanny", and write exactly the way I think I should write. And if I am censored, they will know where to find me.
Good night
Sabdarmish Yehuda
Yehuda:
As usual, in the absence of arguments, you descend into personal slander.
Then cry about being censored and preface all your comments with the sentence "I hope I don't get censored" while ignoring that you can simply decide not to be censored by maintaining a proper discussion culture.
I responded after reading all your comments here
How smart you are, Mr. Point. If some new big bang starts, it will probably be with a singular point like you. You really fill the background of the revered Michael.
After you read my previous response and are ready to respond to it other than to say Amen to Michael, who is dear to all of us, I will perhaps be ready to address your words.
Good Day
Sabdarmish Yehuda
Yehuda, you are pitiful.
By the way, Yehuda:
Now - you hear about Science, maybe submit the article to them?
Come on, Yehuda.
okay, well.
The truth is that I answered all your questions and also that there is a very serious basis (much more serious than the basis of your article) for the questions I asked, but I was not surprised by your response. I did not expect you to understand.
To Michael
You didn't answer even one question from everything I wrote, sah nonsense and silly and shallow smearing.
You are talking about errors and nonsense about specific gravity, what is the connection anyway?. And I, to a person like you I was supposed to submit my essay to the reviewer?, that you will be my nanny?
I hope that there will still be people who will read my previous response from today and ask the same questions I asked.
Good night
Sabdarmish Yehuda
Yehuda:
I really don't have the strength to deal with crazy ideas.
Dark mass creates a force of attraction and not a force of repulsion, therefore there is not an iota of logic in your proposal.
what? Didn't you know that?
I saw your blog article and it doesn't even come close to physics.
I don't have the strength to deal with the multitude of errors he presents and also what I wrote about him in the comments I made before based on hints you scattered about him turned out to be completely correct.
For example - there is no reference in the article to the fact that the movement of bodies within gas and under its influence results, in part, from their specific gravity and shape, and the attempt to treat the entire galaxy as interstellar gas ignores (among the many things it ignores, too) this fact.
In general, a person should know how to read before he starts writing.
If you don't know about Nature, about Science, or even about Galileo then you better learn that there is a press that deals with the issues you talk about and does so seriously.
The truth is that even though I believe you didn't read these newspapers - still I don't believe you didn't know about their existence. I also tend to believe that you tried to publish the things in such places and were met with refusal (and I understand why! After all, the multitude of contradictions in your theories was also exposed in the discussions here).
The whole idea in these papers is that the articles that appear in them are peer-reviewed before (but before!) they are published to the general public.
This is because science is not politics. Most of the public does not understand much in the field and is unable to criticize things. After all, even here - on the knowledge site - a long time passed before you started to encounter serious criticism.
The science site is perceived by the public as a scientific site and it tries to meet the obligations that this fact imposes on it, but you do not want to obey the laws and demand that your theories be published without peer review.
Come on! If you were a person who had already proven himself like Einstein, then maybe they would allow you to do this (also not sure! I know of an article by a serious scientist that the site refuses to publish only because that person refuses to submit the article to peer review) but you are not like that!
To my father to Michael and others
I read this article and smile. Smart scientists show how dark energy prevents galaxy clusters from growing
Why is it impossible to accept as logical the similar idea that a dark mass in a similar action prevents the spiral galaxies from growing and spreading into space.
Why is it legitimate to see a cloud of dark energy that prevents the galaxies from expanding and not legitimate to give this role to the dark mass in spiral galaxies?
Precisely in light of this article, I would like you to check again the publication of the article "Stress the Galaxies" as it appears on my blog.
And Michael, I don't try to publish my articles anywhere else because I don't know any other place but my science and science and nature so it is an exaggeration to say that others rejected my articles.
In addition, wouldn't it have been better for you that where I express my opinions, in front of our dear students, you could also show them your response. Is the preferred solution to prevent me from posting," or to allow posting and commenting on the posted things?
Good Day
Sabdarmish Yehuda
http://madaveteva.blogli.co.il/
for cool:
I did not answer according to the second law of thermodynamics.
No one claimed that dark energy is added to the universe out of nowhere. The claim is that it exists as "is" and has nothing to do with "isn't".
The point is that entropy is not only related to temperature.
The mathematical interpretation of the increase in entropy is a transition to a state whose probability is higher.
You are also welcome to read here:
http://www.mdpi.org/entropy/papers/e10030150.pdf
light:
There is no proof in physics and usually there is only indirect evidence.
Have you ever seen a photon or an electron?
"increases entropy, and only it"
That is, it is impossible to exploit the dark energy according to your theory
to Judah,
The thing is, if there really is dark energy that comes out of nowhere, it breaks the law of conservation of energy. Then it can add energy to the universe system, the question is whether to define the energy as work or as heat.
DA According to the simple universe theory, the assumption is that dark energy is actually the gas pressure that causes it to spread and the universe to expand. According to your theory, dark energy does increase entropy, and only it
A question for the cool responder
Why is this so important to you, because once they have created energy out of nowhere with all kinds of help, you will already want something screwed up in their approach. What about the law of conservation of energy/mass?. They with such hocus pocus will justify their every nonsensical idea.
I also don't understand how dark energy prevents the expansion of galaxies when its entire theoretical function is actually to justify the accelerated expansion of the universe.
Good Day
Sabdarmish Yehuda
Yehuda,
The main thing is that you are consistent and determined on the subject of dark energy.
I too would like to see proof of its existence and not just an inference of its existence because it fits equations.
to the cool responder
Your question is difficult and interesting. At first glance, I do not agree with Michael's statement that energy introduced into the system will not change the entropy.
But you need to check this, it is something that happens throughout the universe and the answer is not simple.
Good Day
Sabdarmish Yehuda
You gave me an answer using the second law of thermodynamics, which is more of a principle than a law, especially when you have energy that comes from nowhere.
That's why you can't say that the "loss of energy to heat" is necessarily a loss of energy, because it's energy that didn't exist, so it might actually decrease the entropy
To the cool commenter:
Did you read comment 11?
Laugh or cry?
And my question is still unanswered
To all our dear students
I have no problem with you going there to read, but if my father meets you on the way, tell him that Michael sent you there and not me.
Good Day
Sabdarmish Yehuda
And more for the students:
Since the comment mechanism is a bit chatty recently and it is difficult to navigate directly to a response that has already been given in the past, I will quote a response that I have already written in the past as a summary of my reference to some of Yehuda's theories.
I'm doing this because I'm not going to bother re-commenting on his site that was opened just to avoid this kind of response.
Yehuda presented his teachings at this link:
https://www.hayadan.org.il/sevdermish-on-gravitayion-part-2-1505078/
This is an article that was written long before I joined the activity on the site, so I didn't respond to it until recently - after I found it thanks to Hogin's response.
The comments I made to him there do not encompass all my reservations because I raised most of the reservations in the discussions I encountered before, even though they started later.
The first discussion in which I responded to Yehuda's words about the idea of the "simple universe" is this:
https://www.hayadan.org.il/could-antimatter-be-powering-super-luminous-supernovae-1612072/
I suggest you read here the discussion I had with Yehuda.
I think it's interesting.
Another discussion took place here:
https://www.hayadan.org.il/glast-in-orbit-1306088/
Here I gave Judah an opportunity to show us how much he knew about particle collisions - a phenomenon on which he based his entire teachings.
This happened, as mentioned, even before I read what was said in the first link I provided.
And just another word for the students:
If the jumble of words you will read on that website will confuse you, I suggest you just ask yourself why no serious scientific website is willing to publish it.
The cool commenter:
Energy does not change entropy.
Entropy changes as a result of changing the distribution of mass and energy.
The right question is therefore - does the continuous action of dark energy increase entropy.
The accepted answer to this question is: "Yes. The action of energy always increases entropy."
The problem is that so little is known about dark energy that it is difficult to answer with confidence.
For example, I read about a proposal (and all there are currently in this field are proposals for theories - no more) that the fact that dark energy spreads the mass everywhere is essentially equivalent to a re-creation of the absolute emptiness that formed the starting conditions of the Big Bang - that is, that there is an identity between infinite entropy and the absence of entropy But all this, as mentioned, is far beyond the knowledge we have today.
To the dear students
Michael tries to convince me to respond but my father asked me to try not to. So those who want to read several articles on the subject should access my blog but only when you are older.
And as for the power required, well just saying...., sorry, I promised.
Sabdarmish Yehuda
Science and Nature - Sabdarmish.
I hope you remember, students.
Movement requires force.
First it was suggested to you that there is no power.
Since this claim is hidden, they change because and now it only disturbs that the power lies in the emptiness and this, even though it is known that the emptiness is not empty and it is "infested" with the activity of virtual particles that are continuously created in it out of nowhere and disappear suddenly as if they were not there.
At some point you will have to understand the fact that the universe is complex and not simple.
You will also need to understand that scientific theories have to agree with the findings and that science is not done in vain.
Yehuda, Michael, if you don't know how to answer the question I asked, it only means that our governments are not "big" enough to make bombastic decisions about even energy, etc.
To our dear students
I have no doubt that the bodies in the universe are expanding in an accelerated manner. But to explain it with dark energy?, power and energy lying in emptiness?, what is this nonsense, why not say if it is divine power?, don't you see both?
But maybe Michael is right, why spoil you, go with what is written in all the books, get high marks and be happy, because I don't want to spoil your scientific innocence.
When you are big and brave, go to my blog and you will see a slightly different opinion.
good week
Sabdarmish Yehuda - "Science and Nature"
High school students are asked to read:
Just in case you didn't follow Yehuda's advice and still read his words, I want to remind you that you have already learned that in order to change the speed and direction of movement of a body, force is needed.
That is why there is a lot of logic in the idea of dark energy since we are watching an accelerated expansion of the universe and acceleration, as you remember, requires power.
Someone could decide that this power is not dark but green but that would just be a pun with no real content.
There is, of course, another scenario that may explain the phenomenon, and that is the expansion of space itself - as is believed to have happened during the period of "inflation" that followed the Big Bang.
Of course, regarding the clusters of galaxies (which, of course, extend over quite large distances) - a force is needed to hold their components together (since the components of the cluster move in orbits around their common center of gravity and their speed as well as the direction of their movement are constantly changing).
This force is called gravity. Again, someone can tell you that there is no gravity and that what drives them is the force of crushing but that too would be a pointless play on words.
Hi Yehuda LONG TIME NO SEE...
You asked some questions and I will answer you, in return I expect you to answer my questions 🙂
1. The cause of the expansion of the universe is dark energy.
2. Yes - this is some kind of dark energy.
Now it's my turn - only a decade ago that 'dark energy' was discovered, it was discovered when observations of hundreds of type 1a supernovae taught that they were accelerating away from us. If in a decade (shortened in terms of the life of the universe) they managed to measure an increase in speed (acceleration), it is likely that this is a significant acceleration (which would otherwise be 'swallowed' by the measurement error). 13.7 billion years we are already accelerating, why haven't we reached the speed of light?, when will we reach the speed of light?, where are the relative effects of the speed of light? Regarding time and distance and mass?
Remember Yehuda - a promise is a promise!
And please do not include the second law of thermodynamics in the answer
A question that I am not sure of the answer is:
Does dark energy increase or decrease the entropy of the universe?
I wouldn't celebrate it.. the contingency effect works as well.
Similar simulations show results that are unrelated to the structures seen in the sky today.
In short, remember that the whole thing is still speculative...
Hopefully I won't be censored.
Perhaps there is a confirmation or proof here of the accelerated expansion of the universe (although they did not clearly explain to us how they reached this conclusion). What is the cause of this?, is it some kind of dark energy?, such a thing is not clear from the article.
Now, here is food for thought for the brave, (high school students are asked not to read) –
Drawing the conclusion that there is a force of repulsion at large cosmological distances is a conspiracy just like saying that there is a gravitational force at large distances as above. There is no proof for both! The cosmological principle cannot be a proof of a physical formula (in this case gravitation) beyond the range of measurements in which it was proven.
If so, and since gravitation and repulsion contradict and cancel each other out, wouldn't it be better to say that gravitation does not exist at large cosmological distances and therefore there is no need for repulsion? Food for thought.
Shabbat Shalom
Sabdarmish Yehuda