Thread: Big Bang and Accelerating Expansion Theory

I have been trying to understand the latest theory of how the galaxies are actually expanding away from each other at an accelerating speed (rather than at a constant speed which has widely been accepted until recently).

According to what I have seen and read, the followers of this observation explain the phenomena on "dark energy" which is resposible for the vacumn of space pushing groups of matter away from other groups of matter.

Here's my problem: If this is the case, how does matter ever gather together in large quantities in the first place if this is true? If one of the properties of a vacumn is to push bodies of matter away from each other, then its hard to conceive of enough matter getting together to create the Big Bang in the first place.

Strangely enough, I have never heard one supporter of this theory explain this question, nor can I find any postings on this subject on any forum board. Am I the only one missing something obvious?

I've heard many theories that there was nothing before the Big Bang and that all the matter in the universe was instantaneously created during the Big Bang, blah, blah, blah. Is this such a widely held belief that noone questions it anymore?

Other theories suggest that the matter in our universe came through a wormhole during the Big Bang. Fine, but then that matter still had to conglomerate in the alternate universe. Unless the alternate universe has different laws of physics, all that matter would never be able to gather due to dark energy.

Anways, not that I'm a cynic of the Big Bang theory, or trying to hint at a higher power, I'm just trying to figure out how so many scientists can accept this property of dark energy without answering the question of how matter ever gathers in large quantities if dark energy tries to keep it away from each other.

Seems to me that a more reasonable explanation is necessary.

Any enlightenment would be appreciated.

Maybe Dark energy came after Big Bang???

That's why scientists are always trying to study and examine the cosmos to better understand just how it really works. There's not one scientist that says that everything is known. That leaves allot of room for exploration and studies about how everything works. Theories will come and go but they are based upon the latest scientific studies that are available to them. More exploring, more theories and more understanding are ahead.

Originally Posted by flying_kiwi

Maybe Dark energy came after Big Bang???

This would imply that the Big Bang was the start of everything, rather than just an event in the universe. Perhaps this is the part that I have a problem with.

Originally Posted by cosmictraveler

That's why scientists are always trying to study and examine the cosmos to better understand just how it really works. There's not one scientist that says that everything is known. That leaves allot of room for exploration and studies about how everything works. Theories will come and go but they are based upon the latest scientific studies that are available to them. More exploring, more theories and more understanding are ahead.

I agree.

The problem I am having is that scientists are eager to accept the "dark energy" explanation without explaining the obvious contradictions. From my point of view it looks like they are choosing to ignore certain things to fit their theory -- but since I know many of them are respected scientists, this does fit their profile. Either I am missing something that is obvious to everyone else and doesn't need to be explained, or the theory that the Big Bang happened out of "nothingness" is now widely accepted and doesn't need to be challenged.

If indeed the universe is expanding at an accelerating pace, it would be less surprising to me if it was just left unexplained than to create a theory with contradictions and then to ignore the contradictions.

Anyways, I have begun to repeat myself....

The acceleration theory is wrong. The big bang theory is wrong. Dark energy doesn't exist. All these things are mental concepts created in a human brain. No other organism in the universe would have any use for them. They wouldn't make sense. Interpretations of measurements of energy our body's senses experience and weave together to create reality. There is no such thing as three dimensional space, or time, these things are just electromagnetic signals passing through nerve cells, and the ways we experience them and the names we give them. There is no reason why our interpretation of our environment should have any true correlation to what actually exists. It is quite understandable that the universe should come from nothing, since nothing is a mental concept. It only makes sense in the brain, and it does not exist outside of the human mind. And this universe is not human, so why can't it extend in ways beyond our mental processing capabilities. Why should we be able to understand it? If we are unable to look at our environment and predict how it should function, that is because our limited subjective existence does not allow us to see things as they actually are.

I dont know about space not existing, but I am sure that time doesnt exist, humans just made it up.

gravity on earth causes objects to be attracted at 9.8ms². so in order to for something to travel away, there must be anti matter.:

matter attracts other matter
antimatter repels mattter

Originally Posted by jmoore1966

Here's my problem: If this is the case, how does matter ever gather together in large quantities in the first place if this is true? If one of the properties of a vacumn is to push bodies of matter away from each other, then its hard to conceive of enough matter getting together to create the Big Bang in the first place.

Strangely enough, I have never heard one supporter of this theory explain this question, nor can I find any postings on this subject on any forum board. Am I the only one missing something obvious?

The effect of expanding space on matter is very small much weaker than gravity however over intergalactic distances it adds up, there is much more space than matter.

[/quote]
The effect of expanding space on matter is very small much weaker than gravity however over intergalactic distances it adds up, there is much more space than matter.[/quote]

That doesn't address the question. That attempts an explanation as to why matter is accelerating away from other matter. It doesn't explain the question of how matter ever gathered together in the first place in signfication quantities to create a big bang if the natural tendency of space is to have matter accelerate away from other bodies of matter.

Is the expansion really accelerating? Consider the following analogy:

A trucking company just started monitoring the movements of its trucks by GPS. The dispatcher keeps track of two units: one (A) averaged 50 k/hr in the last 4 hours, the other (B) averaged 100 k/hr over the past 4 hours. Both trucks left base 8 hours ago. She assumes, therefore, that A should be 400 k from base and B should be 800 k away from base, if, that is, both maintained their present speeds the whole time since leaving base.

But after asking the drivers their positions, she learns that A is 420 k
away instead of 400, and B is 840 K away instead of 800. The dispatcher
concludes from the drivers’ reports that some time after leaving base both trucks had moved faster than their latest averages would indicate. The question is, are they accelerating now, that is, did they accelerate during the LAST 4 hours or were they going faster during the FIRST 4 hours after leaving?

She knows from the GPS record only about the LAST 4 hours - that A
traveled 200 miles in the last 4 hours. She doesn’t know how fast A was going during the FIRST 4 hours. If A is 420 miles away now, then obviously A was traveling faster than 50 k/hr sometime during the FIRST 4 hours and has slowed down.
Likewise with B. If the GPS record shows that B traveled 400 k in the last 4
hours, but is 840 k away now, then it is clear that B was also moving faster than its most recent average sometime during the FIRST 4 hours, and has been slowing down recently.

Could this be an analogy for the expansion rates of space?

We have some data:
a. many observed galaxies;
b. redshifts on a continuum - original elemental waves increasing in observed lengths;
c. brightnesses decreasing according to the inverse square rule;
d. the relationship between the redshifts and the brightnesses has recently
been found to be other than expected from earlier Hubble-type comparisons.

What was found, for example, was that galaxy A’s redshift was twice that of galaxy B’s, and also the time for the SN in A to reach peak brightness was proportionately twice as long as it took for the SN in B. But SN A, instead of being 1/4 as bright as SN B, was dimmer than expected. The proportions were different.

The data is testable and few question their accuracy. It is the *interpretation and implications* of the data that I am saying the truck analogy may call into question. The common interpretation is that the rate, at which space is expanding, has been *accelerating* in the last 5 billion years. I’m saying: Using the same data and the truck analogy, that expansion has been *DEcelerating* recently.

Point to note:
The redshift measurements are the averages of the MOST RECENT rates of expansion, not the averages over the WHOLE period since expansion started. This corresponds to the GPS measurements in the analogy.

The drivers’ reported positions correspond to the distances arrived at by measurements of the magnitudes of Type 1A SN (using the inverse square rule). From the redshift we know *only the most recent* rates of expansion. But these most recent redshifts don’t tell us whether the rates during earlier periods were constant, or higher or lower. If we assume the rates haven’t changed, but the distances by the other kind of measurement is greater than a constant rate would indicate, then we need to change our assumption about a constant rate.
But if the rates HAVE changed, then, according to the analogy, the higher rates were during the pre-redshift time of expansion, not the most recent part of the total measured by the redshift.

If the analogy holds true, then the rate of expansion is SLOWING down, not
accelerating.[/b]

Thanks Moe -- Great post. Makes a lot of sense.

Bottom line seems to be noone really can tell what is going on with the current data. I anticipate someone will put some other data together with the latest red shift data and make a breakthrough that will explain it all in a semi-accepted fashion.

It seems that some scientists -- like everyone else -- like to pick and choose how to interpret data to fit their own beliefs -- its just more surprising to me when somoene in the scientific field chooses to do so.

Your question, JMoore, was [[According to what I have seen and read, the followers of this observation explain the phenomena on "dark energy" which is resposible for the vacumn of space pushing groups of matter away from other groups of matter.

Here's my problem: If this is the case, how does matter ever gather together in large quantities in the first place if this is true? If one of the properties of a vacumn is to push bodies of matter away from each other, then its hard to conceive of enough matter getting together to create the Big Bang in the first place. ]]

If my analogy holds, so that (from the data derived from observation) expansion of space is NOT accelerating, then there is no need to look for Einstein's cosmological constant, negative gravity, dark energy, strings or other ways to explain exotic ³unexplainables.² The forces and fields we already know are probably all we need to describe the visible universe and its history. That still leaves us with the question, What was the cause of the effect they call The Big Bang. We may never have more than unprovable assumptions to answer that.

The expansion of the universe to me is just spacetime moving farther and farther apart causing all the matter in the universe to do the same.

if you pain dots on the balloon an then inflate it you will see the dots getting farther and farther apart as the surface of the balloon stretch.

ofcourse balloons never had to deal with spacetime warps.

Originally Posted by vslayer

gravity on earth causes objects to be attracted at 9.8ms². so in order to for something to travel away, there must be anti matter.:

matter attracts other matter
antimatter repels mattter

Nope, that is not what antimatter is. I hope you haven't been picking your scientific knowledge from Dan Brown (Angels and Demons, the most simultaneously scientifically and theologically illiterate book I ever had the misfortune of reading).

E=mc². Matter and energy are equivalent. Matter has mass, and mass distorts spacetime to give the impression of gravitational attraction. So there is a cohesive force between all objects of mass, proportional to the product of the masses divided by the distance between them.

Now, antimatter. Antimatter is misnamed, because antimatter is still matter - it still has mass in precisely the same way that "ordinary" matter does, and it gravitationally attracts other items of matter just the same way. Of course, the antimatter we most commonly deal with are positrons, or anti-electrons, which are very light charged particles exactly like the electrons they are the complement of, and consequently they respond much more readily to electromagnetic forces than they would ever do to gravity. But if there were an anti-Earth consisting of anti-atoms made of antiprotons and antineutrons surrounded by positron shells, then the anti-Earth would not repel its anti-Moon, or even the "real" Earth were they ever to meet.

Now the evidence appears to indicate that possibly at the furthest distances, the most overwhelming force is not a collective attractive gravity, but a collectively repulsive anti-gravity. And the only way to see this happening, given that attractive gravity is a feature of matter and energy, is to postulate an "opposite" form of matter and energy. You see, this is why anti-matter is not of itself repulsive - two particles, a particle and its anti-particle, can be spontaneously generated by a huge concentration of energy. And if a particle meets its anti-particle, they mutually annihilate and are converted to pure energy. It is the same energy for both particles, you see - the normal, regular energy that we see all around us and make use of.

So the only way of explaining a repulsive form of gravity is to imagine that there is an anti- form of energy itself, which would produce its own forms of particles and anti-particles, except that the gravitational force between them is negative, and repulsive.

*********


The trouble with moe's analysis is that it is implying that we assume that since stuff is flying away at a high speed, that it is accelerating. But ever since the galactic redshift was announced (in 1929, thank you Also Known As!), the assumption has been that the galaxies are flying apart, but that this expansion is slowing down under the influence of gravity. The reason I mention this is because I do not know the details of how they came up with this "accelerating expansion" theory, but I do know that it has to be based on evidence, evidence that contradicts the original "slowing down" assumption. For most of the last 70 years, cosmologists have been attempting to determine whether the Universe is open or closed, ie whether there was sufficient gravitational force to halt the expansion and cause the whole Universe to contract again to a Big Crunch (triggering the next Big Bang in the next cycle), or whether it was expanding too fast and that there was just going to be an ever-slowing expansion until the "heat death" of the Universe when all the energy drains out and the temperature returns to zero.

So what I'm saying is that they've always assumed it was slowing down, so if they say it's accelerating its expansion (contrary to all known physical laws), they must be doing so because of evidence. And I think that evidence has something to do with supernovas in very, very, very distant supergalaxies, or possibly quasars (unless they are the same thing).

Silas wrote:
[[The trouble with moe's analysis is that it is implying that we assume that since stuff is flying away at a high speed, that it is accelerating. But ever since the galactic redshift was announced (in 1929, thank you Also Known As!), the assumption has been that the galaxies are flying apart, but that this expansion is slowing down under the influence of gravity. The reason I mention this is because I do not know the details of how they came up with this "accelerating expansion" theory, but I do know that it has to be based on evidence, evidence that contradicts the original "slowing down" assumption.]].

You are correct in that, from 1929 and Hubble till about 1997, cosmologists expected to find that the expansion, which Hubble doscovered, would be slowing down (though Einstein said his theory would allow either slowing down or speeding up. He didn¹t think it could stay constant without an unknown force he called a ³cosmological constant.² He at the time arbitrarily added this factor to his equations because he didn¹t like the idea of an end. After Hubble, Einstein called his ³constant² the biggest mistake of his life.)

Then about 1997, from data re distant Type IA supernovae, those who collected that data, interpreted it to indicate that the expansion rate (which had been slowing down for 8 billion years) started accelerating about 5 billion years ago. I am using the very same data, nothing new, nothing different. But if my trucking analogy hold true, then there is a different interpretation of the same data. Same data, different interpretation.

Their interpretation of the data (that the rate is increasing) requires an unknown force (dark energy) to explain what they observed. And the universe will end in a ³Big Chill². My interpretation of the same data (that the rate is DEcreasing) needs only ordinary gravity to explain what they have observed. And the universe will end in a ³Big Crunch.² If you want ot spend billions of dollars and give hundreds of people jobs, go with the unknow force that has to be found. With my interpretation, gravity is all that is needed to claify Einstin¹s equations and Hubbles discoveries.

Which interpretation do you predict they will go with?

JMMoes

I think I like my explosion theory.

Objects toward the center of the explosion move faster then objects on the outside. From the point of view of the outside object that is slowing down the object closer to the inside appear to be accelerating toward the outside objects.

The outside is slowing and the inside is moving much faster then the inside object, this might give the illusion that some things are accelerating. In fact everything is slowing. Kind of like the car that is moving faster then the rest of traffic while the rest of traffic is starting to slow down. To the cars that are slowing the faster moving car might actually appear to be accelerating. The closer rate is what is accelerating. In the end everything comes back in to harmony and certain distances are kept.

Make any sense?

Silas. I've just read your entry of July 30th. It’s a treat to read a quality entry. Keep it coming.
Scientists generally tend not to make hasty pronouncements on such matters. Professor Fred Hoyle was a proponent of the Steady State Theory (nothing to do with democracy!) for a very long time. OK, so he has long since been found mistaken, but he arrived at his conclusions as a result of scientific evaluation. In the same way, more recent theories have arisen to meet newly discovered data. We're not talking, here, about precipitant school boys having a shouting match. We're talking about dedicated professional scientists who are serious about arriving at 'truth', however approximate that may eventually turn out to be. We non-scientists may understandably find some theories difficult to comprehend. That, of course, is to be expected. Short of setting out to get a PhD in the relevant subject, I guess there's no real cure for it.

Many times theories are based on information that is not 100% accurate, it pollutes the entire equation. Many people are trying to find answers for things that we don't as of yet have a science for. I think until we embrace and explain some things that are just not mainstream we will always be a bit far from the truth. We also have to consider that the universe may have intelligence behind it's design so far beyond the tools we are provided that it would be impossible to understand it. Sometimes the simplest answers are the correct ones.

Originally Posted by (In)Sanity

Many times theories are based on information that is not 100% accurate,

Theories about the real world are always based on information that is not 100% accurate.