Plank Time

[anubisthejackal]

What was the universe like prior to 10^-43 seconds? Is deducing such possible without revamping and/or refining General Relativity?

 

[kyle_baron]

We don't know. This is from Back to the Astronomy Cafe, Table 8 Cosmic Timeline:<br /><br />1. 10(-43) sec. Planck Era. String World. Birth of time and space.<br /><br />2. 10(-36) sec. GUT Era. Strong and Weak forces freeze out.<br /><br />3. 10(-34) sec. End of Inflationary Era. <br /><br />4. 10(-23) sec. Hadron Era. Massive particle soup.<br /><br />5. 10(-12) sec. Four Forces. Temp=10,000 Trillion K.<br /><br />6. 10(-6) sec. Quark freeze-out. Temp=10 Trillion K.<br /><br />7. 10(-4) sec. Lepton Era.<br /><br />8. .01 sec. Nucleons appear as free particles.<br /><br />9. 1 second Radiation Era. Temp. 1 Billion K.<br /><br />10. 3 Minutes Nucleosynthesis Era. Helium, deuterium, berillium, and lithium appear. <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>

 

[alokmohan]

It was a total chaos then.Temperature was trillion trillion trillion and so on

 

[ashish27]

temperature and density at time of BB was infinite. the universe was a singularity. and i rather think that was a state of order. Chaos is what that prevails now, galaxies floating all over. Just ask the Borg Queen!, haha

 

[dragon04]

<font color="yellow">temperature and density at time of BB was infinite. the universe was a singularity. and i rather think that was a state of order.</font><br /><br />"Macroscopically", yes. "Microscopically", who knows?<br /><br /><b>Something</b> "triggered" the BB. Something very chaotic, perhaps?<br /><br /> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[ashish27]

i like the word "trigger". its cool. what or who triggered the BB? thats the million dollar question today in physics. anyone who answers it (even partly) wins the nobel prize!

 

[alokmohan]

In general theory of relativity , space and timre are not two dfferent things.There is spacetime only which started at big bang.Time dd not exist before big bang.Give me nobel prize.

 

[emperor_of_localgroup]

<font color="cyan">Temperature was trillion trillion trillion and so on</font><br /><br />Gentlemen, I ask you a simple question. Which is more plausible, logical, natural?<br />Temperature suddenly (instantly) rising to trillion trillion trillion degrees? Or temperature slowly rising to trillion trillion trillion degrees?<br /><br />Big bang has gone way too far into our belief/acceptance system. I don't know are we approaching the truth or are we moving away from the truth? Even CBS is starting a sitcom 'Big Bang Theory'. I rest my case. <br /> <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>

 

[kelvinzero]

Are you talking about the very beginning?<br /><br />Who is saying the temperature instantly rose, from what previous temperature, what previous time, and what mechanism are you proposing for a slow rise?

 

[ashish27]

the universe ever since the BB have been cooling and expanding at the same time. theoritical physicists have time & again reached the same conlcusion that if you reverse-motion the universe it starts at infinite density and temperature

 

[kyle_baron]

<font color="yellow"> <br />theoritical physicists have time & again reached the same conlcusion that if you reverse-motion the universe it starts at infinite density and temperature </font><br /><br />And what exactly is infinite density and infinite temperature? There is no such thing! You can extrapolate backwards from the present day to day 0. But, ESTIMATES from this extapolation arise from mathematical guess work, and nothing more. The BB may not have been dense at all, when consicering Brane Theory, with 2 Branes colliding together. <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>

 

[emperor_of_localgroup]

<font color="cyan">what mechanism are you proposing for a slow rise? </font><br /><br />No, I'm not proposing any mechanism by which temperature of the baby universe can rise gradually. I'm just asking which option do people think more realistic considering our everyday experiences. <br /><br />I still don't understand why do we have to have an infinite density at a single point? We know temperature can make a sudden jump if there is an 'explosion', but in that case 'matter' is already existing. <br /><br />What bothers me is we'd never be able to prove big bang theory is wrong, and the theory is being integrated into our belief system. As a result the correct theory, if there is one, most probably will never see the light of the day. <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>

 

[agent99]

emporer_of_localgroup<br /><br /><font color="yellow">Big bang has gone way too far into our belief/acceptance system. I don't know are we approaching the truth or are we moving away from the truth? Even CBS is starting a sitcom 'Big Bang Theory'. I rest my case.</font><br /><br />If it's a CBS sitcom then the big bang is not what you think it is, it's a big burp. The big bang theory although nice and simple, fails to convince me of anything other than it's an answer based on "we don't really know because we were not there" principle. Some argue it's proven by the redshift observations, but I don't think that is correct. Space has physical properties, just look at what Einstein said. Redshift to my thinking is just a natural consequence of light seperation over distance, great distance. Then there are statements like "everything is moving away from each other". But that isn't true either. Andromeda and the Milkyway will one day be interfering together. Then there is "the great attractor" in which a series of galaxies are heading in one direction. What that great attractor is, no one knows as far as I can tell.<br /><br />ashish,<br /><br /><font color="yellow">the universe ever since the BB have been cooling and expanding at the same time. theoritical physicists have time & again reached the same conlcusion that if you reverse-motion the universe it starts at infinite density and temperature</font><br /><br />That sounds more like a mathematics conundrum than a real world deduction, imo. <br />It's a mathematics conundrum because of the "infinate" conclusion mathematicaly speaking and law of conservation of energy speaking,<br />It's a mathematical conundrum because it's a conclusion based from out of purely mathematics alone. No perseptional imagination needed. One thing Einstein said about this was that our imagination is more important than knowledge. The reason why he said this is that it takes the imagination to "visualise" the working mechanisms

 

[emperor_of_localgroup]

<font color="cyan">If it's a CBS sitcom then the big bang is not what you think it is, it's a big burp. </font><br /><br />Hahahaha, I know they are just using the name big bang. It's a sitcom. Though I'm glad a scientific term is used for a show for ordinary people.<br /><br />When I listen to televangelists while channel surfing, I have to wonder, do these people really believe this absurd stuff they are preaching to thousands of people? Sometimes it appears the evangelists really believe every words in the bible. <br /><br />There are people who completely believe the mathematical deduction of what happened in the first 10^(-43) sec or even in the first 3 sec of big bang. As if this is exactly what happened, exactly how the universe started, pin pointing the exact moment of birth of the first elementary particle (Adam). Only thing they have but the evangelists don't have are the mathematical tools to back them up. Let me add to this. In mathematical models oversimplication is the way of life, how can one exactly model an event that took place billions of years ago. There may have unknown factors that could influence the model which are currently beyond our imagination.<br /><br />Well, I'll keep an open mind and keep reading all theories possible and impossible regarding the baby universe. I know I'll never find the correct answer. <br /> <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>

 

[emperor_of_localgroup]

I have no argument against using BB as one POSSIBLE start of the universe. But not as THIS IS THE WAY the universe started, as many people blurt out events of BB like baseball statistics as if this is exactly what happened initially. <br /><br />I understand currently BB is the only viable theory which makes some sense and there are some observed data to support the theory as lightly as patting on the back of BB. We needed a lion but since we couldn't find a lion we substituted a cat for the lion, it may even be a mouse not a cat.<br /> <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>

 

[kelvinzero]

<blockquote><font class="small">In reply to:</font><hr /><p>what mechanism are you proposing for a slow rise? <br /><br />No, I'm not proposing any mechanism by which temperature of the baby universe can rise gradually. I'm just asking which option do people think more realistic considering our everyday experiences. <br /><br />I still don't understand why do we have to have an infinite density at a single point? We know temperature can make a sudden jump if there is an 'explosion', but in that case 'matter' is already existing. <br /><br />What bothers me is we'd never be able to prove big bang theory is wrong, and the theory is being integrated into our belief system. As a result the correct theory, if there is one, most probably will never see the light of the day. <p><hr /></p></p></blockquote><br /><br />I would go for the assumption that the universe started very small and hot for some unknown reason rather than assuming for a long period the universe was heated by an unknown physics.<br /><br />I dont think the big bang specifies there was a point of infinite density or actually claims to know what the beginning was. It is really about how the universe has evolved since. For example we are pretty happy with the conclusion that the universe is expanding right now, so using the current laws of physics we can extrapolate backwards to predict the universe was denser in the past. But if it gets dense enough it reaches energies that we are not familiar with the physics of. So we bash some particles at those energies and confirm their physics, and this allows us to extrapolate back further till once again we enter realms we need more experimental evidence to understand.<br /><br />You see what Im getting at? We are working backwards by assuming current physics held in the past, not forwards from some hypothesis of the absolute beginning, or even making the assumption there was one.

 

[R1]

I've been trying to take a closer look at BB timelines and schedules, and I'm wondering <br />where is the alleged high temperature coming from?<br />it seems like particles of mass did not even exist yet either, so how can gravity separate from<br />something that doesn't exist?<br />or are whatever particles existed back in the beginning massive? and if they were<br />then wouldn't they need to be moving very rapidly in order to create heat? <br /><br />edit: Actually It seems to mee like in the beginning there was little or no temperature, and no gravity and no mass. Then what about color charge and flavor? I think colors and flavors had to exist first. <div class="Discussion_UserSignature"> </div>

 

[ajna]

I'd see that state as an entanglement of the universe's dimensional matrix before it unfolded. And if oldschoolmojo (in 'the expanding universe thread' by ejohns0338) is right about a universal magnetic multipole (detected in the microwave anisotropy data), it unfolded 'there&then'.<br /><br />What caused anything like that to happen is anyone's guess. It WAS caused by something, and that something's universe is bigger than ours. Otherwise it happened because of nothing, and that has yet to be seen in science.