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Messages - Aeris

Pages: [1]
1
Physics, Astronomy & Cosmology / Re: What do we know about Dark Energy?
« on: 15/01/2022 10:36:11 »
Hey everyone. It's been awhile since I actually posted anything on this page. y stupid computer didn't actually show me any of the newer posts until like a week after they had appeared and even when I finally saw them, I was too occupied with my college work to get around to properly responding to any of them. I also didn't know enough about Dark Energy to really comment on any of the answers posted so I just wanna take the time to thank everyone for looking over my questions and responding to them and best as they could :)
The following users thanked this post: Eternal Student

2
General Science / Matter is Apparently Made of Fields, But How the Heck does that Work?!
« on: 15/11/2021 17:51:08 »
Ok so, around two-ish months ago, I was told by a Cosmologist that what we perceive as matter doesn't actually exist and that the alleged particles that we think it's comprised of are actually "Excitations of fields intrinsic to the universe." At first, I didn't think much of what he said to me. I'd heard far crazier things in science before and considering that the four fundamental forces of the universe already manifest as "fields", it wasn't that hard for me to imagine matter doing the same.

At least, that's how I USED to feel... I've given it some more thought and I'm left with only this to say.

What. The. Actual. HELL?!

Seriously, what in the fabrication of an afterlife that is hell does this actually mean, and more importantly, how does this actually work? Like, particles are just field excitations right? What the heck is exciting them? Where are these fields even located anyway? Are they these physical/metaphysical regions of space that we can travel to? Did these fields always exist, or were they put together by someone/something? Are there fields for antiparticles as well as regular particles? Is there one Electron field for every single Electron in the entire universe, or is every single Electron in the universe a part of a single field? How does particle decay tie into all of this? Does Dark Matter get its own field as well? What about Atoms and Molecules? Where do they fit in all of this? Seriously, I cannot stress how much this single statement destroyed everything I thought I previously knew about matter and the sub-atomic world.       
The following users thanked this post: Zer0

3
General Science / Re: How can photons have momentum but no mass?
« on: 16/10/2021 20:30:53 »
Quote from: Eternal Student on 15/10/2021 23:13:31
Hi.

Quote from: Aeris on 15/10/2021 18:10:02
Ok, so if light isn't energy or matter (I'm at least 99% confident in saying that light most definitely is not matter), what the hell is it then? 
    At school level (let's say under 16 years of age).  Light is one form of energy.  That's it, full stop.  ....Well, almost, for some UK examination syllabuses  energy is NOT considered to have forms, there are just some stores of energy - but let's not worry too much about that for the moment.  If you said light was one form of energy you'd get that marked right most of the time.

    At University level, it's much harder to define what energy is.  I think you (Aeris) have started other threads about this.   Energy becomes a much more abstract quantity - just some number you can calculate and it stops being considered as any sort of substance or physical thing in it's own right.    With this idea, light isn't made of energy because energy just isn't any kind of physical substance.  Instead, light just carries some energy or has some energy value associated with it.

   So what is light at University level?  Well, it's interesting and I'm sure I don't have the definitive answer.
We want both of these things:
1.   It's something that exhibits both wave-like  and particle-like properties.
2.   On macroscopic scales, classical Electric and Magnetic fields seem to permeate all of space and light is a special type of oscillation or excitation in those fields.

   There is a model describing light as a classical electro-magnetic wave, which is true enough or good enough for most purposes at University.  It doesn't describe the particle-like behaviour all that well, we need some sort of qunatum model for that.

  And we often end-up with this conclusion:
3.   A quantum field theory seems the best model to explain what light is and how it behaves.  There is a fundamental field (which permeates all of space) for every particle in the standard model of particle physics.   So a photon is a quantised excitation of the underlying electromagnetic (or photon) field.
   I'm sorry, that probably doesn't help much.  It just says that fields may be the most (or the most so far) fundamental things in the universe and all particles are just excitiations in these fields.  This is unlikely to be the final story, it's just one of the best and most up-to-date that I'm aware of.  String theorists probably have their own opinions (which I know incredibly little about).

Best Wishes.

You know, it's funny. I LITERALLY just had an online chat with a cosmologist yesterday evening and one of the things he said to me was that matter, as we currently know it, may not actually exist at all. Fields exist, and particles such as Protons, Neutrons and Electrons are merely excitations of those fields (or something like that, I don't 100% remember what he said and my dumb ass was too lazy to write anything he said down). At any rate though, I do understand most of what you're saying. Mostly that we have very little idea what light actually is.
The following users thanked this post: Eternal Student

4
New Theories / Re: Is the sun photons?
« on: 15/10/2021 19:00:56 »
Quote from: Black hole on 15/10/2021 18:35:42
Quote from: Aeris on 13/10/2021 15:51:16


1. So... Photons lack mass
   

Where do you get the impression from that Photons do not have mass ? The Sun is a huge ''ball'' of photons and the Sun has mass . If you add photons to a block a metal , the block gains mass .
Perhaps you need to learn physics before you make such statements ?

Ummm... the Sun's made out of Plasma buddy, not Photons. It merely radiates the energy it generates from the Nuclear Fusion processes happening in its core as Photons (and other cool stuff such as Gamma Rays and UV).

Also, yes shoving a bunch of Photons onto some metal will make it heavier. That wasn't what I was asking. I was asking how light was able to move matter (like metal) through momentum which I didn't know the location it borrowed it from.
The following users thanked this post: Zer0

5
General Science / Re: How can photons have momentum but no mass?
« on: 15/10/2021 18:13:45 »
Quote from: Eternal Student on 15/10/2021 17:19:00
Hi again.

I was also going to address this point:
Quote from: Aeris on 14/10/2021 18:24:26
Tons of people have come to give their answers to my past questions (my question about the true nature of energy is like 3 pages long with over 40 replies). I've also never seen a single person drop even a little bit of advertisement into their answer once, but maybe I didn't look hard enough for it at the time.
   This thread, I think is the one you refer to:    https://www.thenakedscientists.com/forum/index.php?topic=83150.0
It didn't have as many responses as you might have thought.  It's showing as two pages and if I counted correctly, only 8 people (plus yourself) commented on it.  Half of these people were moderators, so there were almost obliged to engage with people who post.

    I often look at the statistics on the main page when I first log on.  Quite often I'll be the only one loged on.

As regards advertising.  Here's some info from a moderator on another thread:
Quote from: Colin2B on 28/09/2021 08:48:38
.....Then came the realisation that internet advertising was good, coupled with the development of bots and we started getting 200 spams a day - more than legitimate posts. Even now the main site can get over 500 a day and recently one of our mods took down 64.....

    Don't get me wrong.  I quite like this forum but it's worth recognising that it is actually a really small forum in comparison to many others.

Best Wishes.

Meh. Still a more reliable site to learn about science than anything else on the Internet I've come across (not to mention way friendlier).
The following users thanked this post: Zer0

6
General Science / Re: Questions that Antimatter to Me
« on: 08/10/2021 16:06:49 »
@Eternal Student

I'm sorry if I haven't been as active lately. I've been quite bust with College work and getting as much sleep as possible. I also didn't really have anything to comment on here since A. All of these answers were good and understandable, and B. I don't know enough about Antimatter to discuss it further with anyone here.
The following users thanked this post: Eternal Student

7
General Science / Questions that Antimatter to Me
« on: 04/10/2021 09:56:43 »
Antimatter. It's a thing that exists and it's something that I wanna learn more about. Just gonna jump straight into the questions this time around instead of drawing things out with a long-winded introduction.

Question 1: Why is there more matter in the universe than antimatter? Like, you can't make matter without also making an equal amount of antimatter, right? Where did it all go during the period of time right after the big bang (this is the most unreasonable questions of the bunch, so if all we have at the moment are theories/guesses as to what the actual answer may be, I'll still accept them)?
Question 2: If regular matter has a positive electric charge, and antimatter has a negative electric charge, what would matter with a neutral (or no) electric charge be called? Does such a thing even exist? CAN such a thing even exist?
Question 3: In the early stages of the universe right after the big bang, the energy density of space was high enough to support energy's spontaneous transformation into matter, and a watered-down version of this process has been replicated in particle colliders by smashing two photons (AKA carriers of electromagnetic energy) into each other to create matter and antimatter particles. Despite originating from the same place however, matter and antimatter have different properties from each other (the main one of course, being the aforenamed difference in electric charge). How can antimatter have different properties from regular matter if they were both made from the same stuff as each other?
4. Is antimatter a necessity for our universe to exist and be the way it is? Like, what does antimatter do for us that regular matter (or even dark matter) can't? How different would life be if antimatter straight up didn't exist, both in theory and in reality?           
The following users thanked this post: Zer0

8
General Science / What is Energy? Like, seriously, what is it?
« on: 23/09/2021 15:40:30 »
So far, I've made three posts on this website and two of them were about energy (one was about firelight and the other was about the law of conservation of energy). I received some really helpful answers for each of these posts... but I also received a new question that's been eating me alive for these past several days.

What the actual hell is energy?

Like, seriously. I understand real-life is nothing like fiction where characters and machines can shape energy into tangible spheres, beams and various other shapes, but I honestly can't take the notion that energy is merely a property of a physical system seriously anymore given everything I've learnt about it.

Ok, ok... first of all, energy can change forms... no, hold on... energy can EXIST in multiple forms. Light, thermal, kinetic, sound/vibrational, electromagnetic/radiant, etc. The ability to change forms, you know, TRANSFORM feels like something a physical thing that doesn't just exist as a property of a system has the ability to do. Hell, matter has the ability to do just that, and matter, like it or not, is an actual thing that we can define and see.

Speaking of seeing things, light. It's something we can see with our eyes and it can exist in the form of a particle called a photon, and let me tell you these buggers can do some pretty crazy stuff. What kind of crazy stuff though? Well laser beams (which are made of photons of light) have the ability to defect matter to the point that it either ruptures, ignites or even both, and objects such as crystals and mirrors have the ability to reflect those beams in the opposite direction they were pointed at. Even crazier than this however is a photon's ability to move, like, actually straight up apply motion to matter by transferring their momentum to them.

Let me repeat that. Photons, which are LITERALLY made of energy and have no mass whatsoever, have the ability to apply force to physical objects and cause them to move. Solar sails use the energy produced from the Sun to achieve a speed of 18,600 miles per second (or 67,100,000 mph if you wanna get technical). Yes, the amount of energy we're dealing with here is unreasonable by the standards of our planet's various nuclear plants and wind turbines, but the point still stands. Light shouldn't be able to move anything like this unless light itself was also a 'thing'.

And finally, just to top it all of we have the Einstein's famous E = MC² equation, which gave rise to the notion that matter (or I guess mass in this case) and energy were one and the same and could be transformed into each other. Now, we already have tons of examples of this formula working in one direction in the form of combustion, nuclear explosions, nuclear fission and nuclear fusion, but we've also seen scientists achieve the opposite affect and turn energy in the form of photons into matter and antimatter particles via a particle collider. The Big Bang also created matter out of energy, and we even have evidence of this in the form of the Cosmic Microwave Background.

So energy can exist in multiple forms, physically interact with matter as if it were something tangible, can be turned directly into matter and vice-versa and some forms of energy like light, sound and heat can be perceived by the naked eye (ok, that's a lie. Only light can actually be visibly seen by the human eye, the other two require special technology). If energy really can't be considered a 'thing' the same way that matter is often considered a 'thing', why does it have any of these properties? Why can I clearly feel and see its effects on the world around me? What actually is energy?       
The following users thanked this post: Zer0

9
Chemistry / Re: Where does firelight come from? And other burning questions...
« on: 13/09/2021 17:46:09 »
Great answers from both the Bored Chemist and the Eternal Student on my blue flame query. Thank you guys so much :)
The following users thanked this post: Zer0

10
Physics, Astronomy & Cosmology / Re: Did the Big Bang Break the Second Law of Thermodynamics?
« on: 12/09/2021 13:48:36 »
Quote from: Eternal Student on 12/09/2021 11:45:34
Hi again.

Quote from: Aeris on 12/09/2021 10:18:17
Meh, I'd rather have the universe reset it self indefinitely at random than stay dead forever (heat death).
   As discussed above, that's one possibility (if unlikely).   There are other possibilities which are, in my opinion, just as cheerful.

1.  No one has mentioned string theory yet as far as I can see.
   The Universe we experience seems to have 4 -dimensions (3 space + 1 time).  It is possible that all of this is contained on one brane  (abbreviation of "membrane") as considered in string theory.   These branes exist within a much higher dimensional space  (the exact number depends on which flavour of string theory you are using).  Anyway these branes vibrate and move about in that higher dimensional space.  Sometimes one brane collides with another and transfers energy to that other brane.   
    There are three issues of relevance:   (i)  This could explain something from your first post.  Why did all energy seem to be at one place for the big bang in this universe?  Possibly because it was the point of collision with another brane.
   (ii)  The brane that our universe is on may collide with another brane and transfer some energy to that brane.  While this would seem to drain energy from us and may be the end of our universe, it's the beginning for some other universe which might be just as interesting and valuable as our own,  possibly one which evolves it's own life and they can have their turn.
   (iii)  It's possible our brane may have another collision with some other brane but gain (rather than lose) some energy delivered in a small region.  This effectively gives us some more ordered or concentrated energy and extends our universe's life as far as ever increasing entropy is concerned.  (Although if you were near the region where the collision occurred it could be catastrophic - but let's just look at the potentially positive side).

2.    Black Holes and/or Holographic theory.
    Black Holes are truly interesting objects.  Most of the current thinking is that General relativity (GR) simply breaks down at the singularities of a BH,  so we might have some extremely dense matter within an event horizon but it won't be infinitely dense or "singular" in the mathematical sense.    However, suppose GR doesn't break down.  In this case we cannot include the central singularity of a BH into our models of spacetime.  Whatever it is, if it exists in any sense, then it is outside of our spacetime.  The possibilities are then endless - if an object passes into the singularity at the central region of a Black Hole does it enter another universe?   Are there other universes already embedded within our own and are we ourselves living in a universe that is inside a Black Hole?
    There's a vaguely related theorem often called the Holographic theory or Holographic principle.  Anyway, the relevance of this is that all the information necessary to create a 3-Dimensional universe can be encoded on a 2-D surface like the event horizon of a Black Hole.

Best Wishes.

Assuming either of these things have even the slightest chance of happening, I will happily take them over heat death any day of the week (except for the part where our universe looses energy from brane collision, that sounds even worse honestly).   
The following users thanked this post: Curious Cat

11
Physics, Astronomy & Cosmology / Re: Did the Big Bang Break the Second Law of Thermodynamics?
« on: 12/09/2021 10:18:17 »
One of the risks is that another round of expansion could start while we are still here, leading to the hypothetical possibility of a "Big Rip":
https://en.wikipedia.org/wiki/Big_Rip

Meh, I'd rather have the universe reset it self indefinitely at random than stay dead forever (heat death).

PS: The universe doesn't really care what you believe.
[/quote]

Well that's a shame :(
The following users thanked this post: Curious Cat

12
Chemistry / Where does firelight come from? And other burning questions...
« on: 09/09/2021 22:26:44 »
Ok so, unpunny titles aside, I love fire. It's one of the most beautiful things to look at and it's my favorite of the four classical elements coined by Greek philosophers. It's also a goldmine of science that singlehandedly taught me more about thermodynamics, plasma physics and chemical reactions then my time at secondary school. There's still a lot about the process of combustion that I still can't fully wrap my head around though, and since this website seems to be full of super smart people that know their stuff, I was wondering if you guys and girls could answer some red-hot questions I have about fire, flames and light.

Q1. Does the light of a flame come from the fuel reacting with heat and oxygen, the combustion byproducts radiating some of their energy away in the form of visible light or a combination of both?
Q2. Why does a candle burn with a (mostly) white flame, and why does a stack of wood and a patch of grass burn with an orangey yellow flame?
Q3. Why does complete combustion yield a blue flame as opposed to the standard orange-yellow flame? I know it has something to do with the perfect combination and amount of fuel, oxygen and heat, but how do all of these things come together to form a blue-colored flame?
Q4. Does a Hydrogen flame always burn blue regardless of incomplete combustion or complete combustion? Why is the flame itself barley visible to the human eye?
Q5. According to Wikipedia, Soot (a byproduct of incomplete combustion) can exist the form of a gas. Is this true? Does Soot have a sublimation-point? If so, how hot would it need to be to exit the solid state and become gaseous?
Q6. According to several sources I found on the internet, an object gains more mass when it gains more energy. Assuming this is true, would that mean getting punched by a fist that's on fire would hurt more than a normal punch?
Q7. What gives each of the flames shown in the videos below their color?

Link to the Wikipedia page on Soot https://en.wikipedia.org/wiki/Soot

Also, not at all related to the questions above, but what is YOUR favorite classical element? I'm curious to hear why.

Thanks :)           
The following users thanked this post: Zer0

13
Physics, Astronomy & Cosmology / Re: Did the Big Bang Break the Second Law of Thermodynamics?
« on: 05/09/2021 08:29:40 »
"The conversation is moving faster than I can follow, so forgive if any of this is repetitive."

Fine by my. Repetition and colorful imagery is pretty much the only way I can learn anything in science

"About posting about Sci-Fi: Just-Chat section is probably best for discussing non-science like "how do light-sabers work?". A few things might be eligible for the main sections like "Is technology X in Star-Trek" theoretically possible? I mean, those guys showed communicators long before cell phones were a thing, but of course the one's in the show don't work via conveniently nearby cell towers, and their range is almost always limited by the plot requirements of the episode."

Neat. I'll post hard science-fiction questions on the main forums, and everything lower than that on the just-chat section on the website


"Probably a pop-version, never something that was once the current state of the theory. There are countless sites, even reputable ones, that describe the early universe as a small speck of sorts. It's smaller, but not small."

"It expanding into empty space is definitely wrong. Such a thing is impossible since that much matter in a small space would form a black hole and it would never expand outward at all. The density of the universe was uniform everywhere at all times, and the expansion is the metric expansion of space itself, not the movement of material into empty space."

Ok. Well at least I won't make this mistake again the next time I describe the big bang theory to someone else.

"The universe will end in heat death. The probability of otherwise goes down with time faster than entropy increases. Perhaps a better way to work what E-S said is to look at it from a multiple world point of view. Anything possible happens in some world out there, so maybe this temporary divergence from heat death happens in some seriously improbably world, but in all likelihood you're not going to measure that one were you to hang around long enough to find out.
Quantum mechanics figures heavily into this discussion and one must be clear on how one phrases a statement. In standard copenhagen interpretation, the universe will end in heat death, period."

The first and last parts of this paragraph seem to state that heat death has a 99.99999% chance of happening and that the other options have such a laughably low chance of happening that they're not even worth considering. Also unsure what you mean by "The probability of otherwise goes down with time faster than entropy increases". Also, also, if heat death really is the most likely way the universe will end, that pretty conforms the theory that this universe's lifetime is its only lifetime, and this pretty much changes my question from "Did the Big Bang Break the Second Law of Thermodynamics?" to "If everything in existence has a cause, what was the Big Bang's cause?". Like what, the universe used to be a collection of empty space and useless energy that one day, for seemingly no reason whatsoever, expanded into a sea of radiation that gave rise to matter and stars, but don't you all worry folks, it's only ever gonna do this a single time and then once it's over and done with, it's dead forever because it somehow created a magical property that makes entropy work the way described by thermodynamics? That sounds difficult for me to believe." 

"Nobody said that. There isn't such a law spanning outside our spacetime. It seems to be a law of our spacetime.
Once again, Sean Carroll seems to publish several articles about some of the speculation in these areas."

What outside? There's nothing outside our spacetime (other universes don't count as they presumably have their own versions of spacetime and are purl theoretical."

Sorry for the late reply btw.

The following users thanked this post: Curious Cat

14
Physics, Astronomy & Cosmology / Re: Did the Big Bang Break the Second Law of Thermodynamics?
« on: 04/09/2021 17:05:01 »
"First of all I am not a moderator or involved with the administration of this site.  My opinion is just my opinion not the law.
It would seem acceptable to talk about some science fiction in the way you have outlined.   Just make it clear that it was based on science fiction and you are asking if there is any real scientific basis for it.   There is also a  "Just Chat" section where the rules are much more relaxed.  Just about anything can go in there."

Ok. Thx.
- - - - - - - - - - -

"I like the fact that you are open to idea that time might very well be defined this way.  Yes, time may be nothing more than the evolution of entropy.   Personally, I think this idea is as good as any."

This actually isn't my idea, but I appreciate the fact that you used it for the sake of making your answer easier for me to understand (I'm honestly not THAT smart lol).

"There are also Physicists examining the idea that time is just an emergent property.   What does this mean?  It suggests that time is not a fundamental quantity or property, instead it could be something that makes sense and can be defined only in larger systems and it is just a combination and interplay of more fundamental quantities.  Example:  "Beauty" is a property that a human being might have but this is an emergent property that only the whole system can have.  If you pull the human being apart, then the molecules don't have this quantity or property of beauty.  They have other properties like mass and volume but not beauty.  Put the molecules together again and you have a bigger system where the quantity of beauty emerges - it can be defined and identified."

That's... a really flipping cleaver way to put it I'm surprised I haven't heard time being described like that more often by scientists. 

"Anyway, time is complicated and we could fill an entire forum talking about what it is or isn't.  (Just to be clear, it's not as if I know what time is any better than anyone else).  Let's just go with your (Aeris) suggestion.  Time is intrinsically linked to changes in entropy.  Modern cosmology does not usually concern itself with what happend before the big bang.  Indeed the very notion of "before" the big bang is hard to define.  For some reason there was a low entropy state and from there entropy was able to increase and evolve.  Considering time as the progressive increase in entropy, time can sensibly be defined from the big bang but NOT before it."

So... cosmologists can't say definitively why the early universe started off in a state of such low-entropy, but they theorize that there was a property in the universe, be it a physical one or even an emergent one that didn't exist until after the big bang, and that was what ultimately kickstarted the universe's quest to establish thermal equilibrium? Am I even close?
 
"Ignoring the complication that you have said "before the big bang",  we could just challenge the idea of conservation of energy directly.  There is another recent thread here where Energy and especially gravitational potential energy was discussed, if you're interested but that will take some time to read.  I'll just take a small section out of this now:"

Yeah, that was a poor choice of wording on my part. Also I had to cut the link out of my reply since for some reason, the website won't let me post a reply with it. It looks interesting though, and I'm gonna read it more thoroughly this evening. Thx.
The following users thanked this post: Curious Cat

15
Physics, Astronomy & Cosmology / Re: Did the Big Bang Break the Second Law of Thermodynamics?
« on: 04/09/2021 13:36:13 »
Quote from: Eternal Student on 04/09/2021 01:31:07
Halc didn't comment on this bit directly.   It doesn't seem that there was any time before the big bang.   There is no reason to assume the first law of thermodynamics or any principle of Physics should apply before the big bang.  "Time" seems to emerge as a property we can identify only after the big bang.

 I'm sorry, what?! Time emerged after the big bang? That doesn't make an atom of sense. Time is quite literally, the process of entropy gradually increasing overtime. What, will time still exist after maximum entropy has been achieved? Is the universe on some kind of eternally long lasting loop of low entropy to high entropy to back to low entropy and rinse and repeat? The idea that conservation of energy not applying to the universe before the big bang also doesn't make sense to me. I don't subscribe to the God theory at all, but I subscribe to the idea of something emerging from nothing, actual nothingness, even less. Just saying it out loud makes me genuinely feel like my IQ is dropping. What's SO special about the period of time before the big bang that energy was able to spontaneously materialize into existence without a given cause?       

 It has happened more than once.  Entropy can be defined using statistical mechanics rather than classical thermodynamics.   In systems where changes are assumed to occur randomly, then sometimes entropy does decrease.   The law of entropy is often regarded just as a statistical law.  For large systems with many particles interacting it is overwhelming likely that entropy will increase but there is a small chance for a decrease.  We don't see the entropy of the entire universe decreasing because that system is so large (contains so many particles and interactions) that the chances of this happening are insignificant.  However, for smaller closed systems within the Universe we can observe entropy decreasing.
    If you're interested look up some articles about the "Poincare recurrence theorem" There are some systems that start in a low entropy state and evolve to what is, on average, a higher entropy state but if the system continues to have random changes then sometimes entropy decreases.  If you wait long enough, then just by random chance, the initial state will have re-appeared again somewhere over that time.

So... entropy, when it REALLY feels like it, can and eventually will decrease all on its own without an outside force acting on it, it's just so statistically unlikely to happen that us humans will all be long dead before we witness it occur on anything higher than a microscopic scale? Does that mean that even after the entropy of the universe reaches its maximum, a new universe will begin again all on its own, thus destroying the notion that heat death won't be the final curtain for all of existence?

Also, side question. I know this is a forum for questions about science, but are questions relating to science-fiction acceptable? Can I at least reference them in my question and ask things like "Could something like this be recreated in real life?" or "Is this particular thing in the story based off of something in the real world?"?

Oh, and thx for the response btw really appreciate it :) 
The following users thanked this post: Curious Cat

16
Physics, Astronomy & Cosmology / Re: Did the Big Bang Break the Second Law of Thermodynamics?
« on: 04/09/2021 13:14:55 »
Quote from: Halc on 03/09/2021 22:30:17
The big bang theory says nothing about the formulation of singularity or suggests a meaningful time outside of spacetime, which is what 'before the bang' is. So while a valid topic, it isn't a big bang topic. To suggest a time before the bang is to suggest that space is contained within time which contradicts relativity's spacetime where time and space are part of the same geometry with neither containing or supervening on the other, as you seem to be doing.

So... am I talking about an outdated/incorrect variation of the Big Bang theory then? I distinctly remember the description of a small, dense super hot region of space containing all of the universe's energy that expanded outward to fill empty space. As for the thing about time, that part I never understood since time is little more than the process of entropy gradually increasing overtime. Assuming the big bounce theory is correct, there's absolutely no reason whatsoever to think that there was nothing in the universe before the big bang began. If that theory turns out to be incorrect though and heat death will be the way the universe actually end, well... actually let's talk about that.



Yes it does. I don't think it was 'heat'. The cosmologists describe the conditions to their satisfaction since yes, such a simple description violates all kinds of rules. Keep in mind that the energy wasn't necessarily positive since there's an awful lot of negative energy present as well, and still is. Energy is conserved only in geometries that are static over time, and our universe isn't described by any static geometry (such as the Milne model). Just saying that the 2nd law doesn't hold in our universe. Carroll put out a paper showing this.[/quote]

So... I'm right then? The big bang really did violate the second law of thermodynamics? Assuming that really is the case, that leaves me with so many other questions. Will the universe stay dead forever once maximum entropy has been achieved? Will time and space even exist after that? What even is space in the context of the big bang? How does all the rate of the universe's expansion and the amount of dark energy needed to drive it fit in with all of this?

Thx for the reply though, I really appreciate it :) 
The following users thanked this post: Zer0, Curious Cat

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