OT - Physics Question on Anti-Matter

[Tnargversion2]

I am curious to know what an estimated force in kt that an ounce of Anti-Matter mixing with an ounce of Matter would be.

Lets compare that to say a standard 20kt nuclear weapon.

I realize this is hypothetical, as this has never been done before, but in theory I am just curious how much energy can be realized from an anti-matter/matter contact.

[Ed Kolis]

OK, let's see... You have 2 ounces of matter and antimatter, that's about 57 grams or 0.057kg, and the speed of light is 300 million meters per second... thus using E=m*c^2, the energy produced in the detonation is 5.7*10^-2kg * (3.00*10^8m/s)^2 = 5.1*10^15 kg*m^2/s^2, or 5.1 quadrillion (the American kind, a thousand million million) joules. What that is in kT I don't know, but I'll try looking it up...

edit: OK, a "ton of TNT", according to Wikipedia, is defined as 1 gigacalorie, which equals 4.184 billion (thousand million) joules (it also happens to equal a million dietary calories - think of THAT next time you sit down to dinner, since there are a million grams in a metric ton, you are eating the energy equivalent of hundreds of grams of TNT! http://forum.shrapnelgames.com/images/smilies/eek.gif Don't let your food a splode! http://forum.shrapnelgames.com/images/smilies/wink.gif)... anyway, since the antimatter explosion produces 5.1 quadrillion joules and a ton of TNT is 4.184 billion, that means that the antimatter explosion is equivalent to... 1.2 *billion* tons of TNT (1,200,000 kT) - which is about 10 times more powerful than any bomb mankind has ever devised! http://forum.shrapnelgames.com/images/smilies/eek.gif (The most powerful bomb was developed by the Russians during the Cold War and it had an estimated output of 100,000 to 150,000 kT...)
(SJ or some other mathematically inclined person, could you stop by and make sure I didn't horribly screw up the math? http://forum.shrapnelgames.com/images/smilies/wink.gif)

[capnq]

Assuming the matter and antimatter can be combined perfectly to cause total annihilation (which is actually a huge assumption), you just have to plug the numbers into Einstein's equation:

E=mc^2

=(1 ounce matter+1 ounce antimatter)(186000 miles/sec)^2

= 6.9192E10 ounce-miles/(sec^2)

Unfortunately, college physics was too long ago for me to remember the conversion factors to change that mess of units to kilotons. Converting ounces to tons gives an order of magnitude around two megaton-miles/sec^2.

Edit: and Ed posted while I was trying to look up the conversion factor before I submitted the post.

[Ed Kolis]

A ton of mass or weight is not the same as a ton of explosive force, so that conversion would have been misleading anyway http://forum.shrapnelgames.com/images/smilies/wink.gif

[capnq]

Well, there's got to be some conversion factor between the two. Whatever that number is, you've still got a big BOOM.

[Baron Munchausen]

Wow, here we have the resources to figure out what it really takes to blow up a planet. The 'death star' beam is stoopid, of course. It takes enough energy to accelerate the planet's entire mass to its own escape velocity to make it explode. For an earth-sized planet this is equivalent to several months output by our sun. (!) A simple 'beam' cannot possibly deliver this much energy. And anyway, if it's delivered from outside, it just burns away one side of the planet, sending the rest spinning away somewhere. The only practical way to really explode a planet is to deliver enough anti-matter to the core to make an explosion big enough to shatter the planet.

So, if someone can figure out how much energy is needed to accelerate the earth's mass to it's own escape velocity, then back-convert that to matter/anti-matter reaction, we would then know how much anti-matter a super-high-tech ablative delivery device (the 'bunker buster' is a toy compared to this problem... http://forum.shrapnelgames.com/images/smilies/happy.gif ) has to deliver to the planet's core.

[PvK]

E = mass x C^2 is valid to give the energy for total conversion from matter to energy. But ya, assuming that's what you can get from an anti-matter bomb is an assumption.

Nuclear weapons kilotons are in terms of equivalent explosive force compared to a certain mass of T.N.T., which of course has its own conversion factor involved. I bet it's not too hard to google up.

There is of course another web page with lots of discussion about what it takes to destroy a planet in various ways.

[Will]

Well, it's a bit more complicated than that. First, it's gonna be a nasty volume integral, since the gravity will be different along points from the surface to the core. Then, there isn't an easy way to tell how much of the energy from the annihilation will be converted to kinetic energy instead of heating up bits of former-earth. And it would probably not be the case that the annihilation happens all at once, or that the energy flux would be uniform across the unit sphere, so you cannot be certain where the center of gravity will be.

Anyway, with all that, I would say that it is safe to assume that the amount of anti-matter needed is bounded by the mass of the Earth. http://forum.shrapnelgames.com/images/smilies/laugh.gif

[Thy_Reaper]

All my data is from Google, so ask it to back me up http://forum.shrapnelgames.com/images/smilies/happy.gif

Earth has a mass of 5.9742 x 10^24 kg.
Escape velocity is 11 km/s approx.
7.228782 × 10^32 (72,278,200,000,000,000,000,000,000,000,000) Joules are needed to blow the planet up.
Based on e = mc^2, 8.0431047 × 10^15 kilograms of a matter/anti-matter mix is needed to detonate the planet, so just inject 4.02155235 x 10^15 kg of anti-matter into the core.
That's 4,021,552,350 million kilograms of anti-matter... ouch.

Well, good luck on getting that http://forum.shrapnelgames.com/images/smilies/tongue.gif

[Tnargversion2]

Ed Kolis said:
OK, let's see... You have 2 ounces of matter and antimatter, that's about 57 grams or 0.057kg, and the speed of light is 300 million meters per second... thus using E=m*c^2, the energy produced in the detonation is 5.7*10^-2kg * (3.00*10^8m/s)^2 = 5.1*10^15 kg*m^2/s^2, or 5.1 quadrillion (the American kind, a thousand million million) joules. What that is in kT I don't know, but I'll try looking it up...

edit: OK, a "ton of TNT", according to Wikipedia, is defined as 1 gigacalorie, which equals 4.184 billion (thousand million) joules (it also happens to equal a million dietary calories - think of THAT next time you sit down to dinner, since there are a million grams in a metric ton, you are eating the energy equivalent of hundreds of grams of TNT! http://forum.shrapnelgames.com/images/smilies/eek.gif Don't let your food a splode! http://forum.shrapnelgames.com/images/smilies/wink.gif)... anyway, since the antimatter explosion produces 5.1 quadrillion joules and a ton of TNT is 4.184 billion, that means that the antimatter explosion is equivalent to... 1.2 *billion* tons of TNT (1,200,000 kT) - which is about 10 times more powerful than any bomb mankind has ever devised! http://forum.shrapnelgames.com/images/smilies/eek.gif (The most powerful bomb was developed by the Russians during the Cold War and it had an estimated output of 100,000 to 150,000 kT...)
(SJ or some other mathematically inclined person, could you stop by and make sure I didn't horribly screw up the math? http://forum.shrapnelgames.com/images/smilies/wink.gif)



Well regardless of how close you are, that still paints a pretty picture. I guess if an Anti-Matter research center proposal comes up in your next city counsel meeting, it would be a safe bet to say no!

Whoops, the magnetic containment field surrounding the pebble sized bit of Anti-Matter failed and wham there goes the county.

[Tnargversion2]

Ok, so in the game perspective, some of the components that utilize Anti-Matter Warheads, we're probably talking about very finite amounts of AM, say less than a gram of the stuff? Other wise we would see one hit one kill damage types correct?

If an ounce of AM and an ounce of matter can produce and energy release something like 10 times that of the most powerful nuke or hydrogen bomb ever produced and we were to successefully hit say an aircraft carrier sized vessel, it would be a safe bet that the aircraft carrier would be nothing but ashes, maybe some mangled trushes and support beams here and there, on one hit.

Next question, how large of a device and energy requirement would it take to contain a gram or less of AM. Hypothetical guesses again are welcome, just trying to visualize this in my head.

[Suicide Junkie]

Energy requirement is basically zero.
The device dosen't need to do any work on the antimatter, but simply provide a potential gradient (electromagnetic) to keep it away from the sides of the container.

The size depends on how good your materials science is... how strong/small/light of a magnet can you manufacture?

[shinigami]

Jumping back to the Death Star beam, something of the sort might be possible, just maybe not on that scale.
Physicists have been able to get atoms to flow along a laser. If the laser is powerful enough to vaporise all the stray atoms in its path and allow anti-atoms to flow along the beam to its end you could have an anti-matter tunneling weapon.

[Slick]

While containment is difficult, making antimatter is much more of a challenge. Making a stable antimatter atom has been done. I'm not extremely current on it, but the last thing I read was that scientists were only able to make a few atoms of anti-hydrogen (antiproton combined with an "orbiting" positron). Capturing this antimatter atom in an electric field is hard enough; and making an ounce is completely beyond our current capabilities. Not to mention that it is a really bad idea because, as the math above shows, a problem with the containment vessel will release lots of energy.

[Randallw]

I just ended up thinking about entropy.

I wondered how you could make a profit because to get the energy out you have to spend energy to make the AM. But then the Positive matter has already been made so you only need to make half of it. From there I started thinking about Fusion power where you get the energy out of sea water because the energy was placed into it at the beginning of time or whatever. From there I ended up considering mining sunlight from a star, but that's not infinite either. Eventually even the star will die. So clearly there is no such thing as an infinite energy source. It makes a clear argument for entropy. One day the universe will die. In about a billion years we might flee to another universe, but clearly even that will die. Which is more disturbing, that everything will die eventually or that I am getting depressed about soemthing that won't happen for maybe 14 billion years http://forum.shrapnelgames.com/images/smilies/fear.gif http://forum.shrapnelgames.com/images/smilies/smile.gif

[Spoo]

Randallw said:
I just ended up thinking about entropy.

I wondered how you could make a profit because to get the energy out you have to spend energy to make the AM. But then the Positive matter has already been made so you only need to make half of it. From there I started thinking about Fusion power where you get the energy out of sea water because the energy was placed into it at the beginning of time or whatever. From there I ended up considering mining sunlight from a star, but that's not infinite either. Eventually even the star will die. So clearly there is no such thing as an infinite energy source. It makes a clear argument for entropy. One day the universe will die. In about a billion years we might flee to another universe, but clearly even that will die. Which is more disturbing, that everything will die eventually or that I am getting depressed about soemthing that won't happen for maybe 14 billion years http://forum.shrapnelgames.com/images/smilies/fear.gif http://forum.shrapnelgames.com/images/smilies/smile.gif



This reminds me of a short story by Isaac Asimov, The Last Question (http://infohost.nmt.edu/~mlindsey/asimov/question.htm).

[Randallw]

hmm, a pretty obvious conclusion.

I can recall 2 stories such as that one. In one a man in a bar is asked how might a robot live forever and they talk about how it would have to upgrade every once in a while but yes it could last forever. The end of the story lingers over one mans young companion.

Another story that comes to mind is after a war where a computer ran everything some men ask its caretaker if it was unable to solve a problem. He answers that he would then flip a coin to decide.

[Renegade 13]

Randallw said:
So clearly there is no such thing as an infinite energy source.

That's not entirely true. Blackholes represent a massive amount of potential gravitational energy that I'm sure could (eventually) be harnessed by mankind. However, physicists believe that blackholes do "decay" slowly over time, losing mass, so it is possible that even blackholes would eventually all disappear, though that would take hundreds of billions or trillions of years.

[aegisx]

Speaking of infinite energy.. you all should enjoy this if you haven't already.

http://infohost.nmt.edu/~mlindsey/asimov/question.htm

[Suicide Junkie]

Renegade 13 said:

Randallw said:
So clearly there is no such thing as an infinite energy source.

That's not entirely true. Blackholes represent a massive amount of potential gravitational energy that I'm sure could (eventually) be harnessed by mankind. However, physicists believe that blackholes do "decay" slowly over time, losing mass, so it is possible that even blackholes would eventually all disappear, though that would take hundreds of billions or trillions of years.

How is it not true?
How do you plan to get anything out of said hole without reducing the hole's mass-energy?

Just because there is a lot of mass there dosen't mean it is infinite in any way. Where "a lot" is only a handful of stellar masses in many cases.

[PvK]

Randallw said:
... In about a billion years we might flee to another universe, but clearly even that will die.



That's like saying you'll surely die of old age in "about a microsecond." I.e., you are off by so many orders of magnitude that you're asking the wrong question, several times over.

It's also based on cosmological assumptions based on far too little evidence, which is the mistake modern science generally makes even when it gets its math right. Not to mention the misinterpretations of people reflecting upon the hypotheses and conjecture of cosmologists. Or the imaginitive leaps of science fiction and TV documentaries.

PvK

[Randallw]

hmm, I thought a billion years was about right before we could actually traverse universal barriers. Well maybe not exactly but the intent was that it would be a very long time.

[aegisx]

Entropy, cold death... if the universe keeps expanding everything will break down eventually.

http://www.physlink.com/Education/AskExperts/ae181.cfm

[Raapys]

Assuming that there were no unknown factors( which there most certainly is ), wouldn't gravity keep the universe from maximum entropy? Is there anything to indicate the universe wont just do the whole big-bang thing over and over again?

I also thought I read somewhere that they'd discovered that light didn't actually travel infinitely, but somehow bended back towards us when it had travelled for some time?

[Phoenix-D]

That's one possibility, but as of the moment the Universe's expansion actually seems to be speeding up, not slowing down..

[aegisx]

Last i heard it was speeding up too. Really, the 'Last Answer' story answers this well http://forum.shrapnelgames.com/images/smilies/wink.gif

So if everything we know now is true 9which is probably isn't), the universe will run out of 'energy' some day.

[Raapys]

Yeah, but when that 'energy' is depleted and everything has 'stopped', gravity will still be there( as far as we know ). What is to stop it from pulling everything together again?

I read the Last Answer. It was a nice read, thanks.

[aegisx]

Gravity would dissipate to pretty much nothing I suspect. Gravity is a force and spread over theoretical particles called gravitons. So as stars, planets, elements, atoms and particles break down, so does the gravitational force. All these things are held together by very strong forces compared to gravity, so if those are breaking, gravity probably isn't a big issue.

Of course, this is just based on my basic understanding and I could be wrong.

[PvK]

According to that theory, the universe seems to exceed the "escape velocity from the Big Bang".

However, this is all rather presumptuous speculative interpretation about the meaning of what we're seeing from our perspective.

A mere few hundred years ago, the general idea was you fell off the edge of the earth once you sailed past the Azores from Europe...

I'm not convinced that modern cosmologists have got it nearly as right as some people might assume.

PvK

[Raapys]

Well, I wont claim to know any better, but I would have thought that if gravity was still there, however 'weak', the particles would slowly start to pull together again; unless something was actually exerting force on them( stronger than the gravity ), keeping them apart.

Anyway, if indeed the expansion is speeding up, that means energy is being continusly applied to the mass in the universe( thus providing the speed increase). Since energy = mass ( right? ), that means further that the amount of mass in the universe is increasing as well? And since all mass has gravity, as far as we know, that also means gravity increases? Thus eventually becoming strong enough to counter whatever other force is pulling the stuff apart...?

My non-existing education got cut short, so I'm a little out of the loop. Please correct me if something's wrong with my understanding.

Also, wont the whole 'expansion speeding up' thing also mean the entire mass of the universe will be traveling at light-speed in a 'few years'?

[Suicide Junkie]

Its not the objects accelerating (IE Kinetic energy), but the underlying spacetime itself expanding.

BTW, if something is at escape velocity, it will never fall back (barring interference from other space objects)... that's because even though gravity is always there tugging on it, gravity is weakening faster than the speed is decreasing.
On a parabolic "orbit", the speed approaches zero as time approaches infinity... but it never quite manages to go negative and loop back. No matter how long you wait, you've always got just a little speed left, and gravity is *just* slightly too weak to stop you.

[PvK]

The Expanding Universe theory is that gravity is too weak to slow down something moving quickly away that is already an astronomical distance away. Gravity gets weaker and weaker the farther something is away. There is a limit to how much its force will ever add up to beyond a certain distance, so if the distance is increasing, and effect of gravity decreasing, things can escape gravity. The question then became exactly how massive is the universe, and how far is it apart, how fast does it seem to be expanding?

However, after many years of trying to figure that out based on all sorts of assumptions (which made sense, but are still just theories), cosmologists are starting to decide that some even more basic assumptions seem to likely be not correct, such as that the rules of the universe remain constant over time and distance...

The idea that we are seeing the universe all receding at increasing speeds at great distance is all based on assumptions about how to interpret the light we see based on a mountain of theories. It's an extremely sophisticated mountain of theories, but it's still an active volcano, so to speak.

PvK

[Suicide Junkie]

As far as the accelerating expansion, sort of.

Consider the balloon analogy. You've got a superstretchy rubbery surface which is being inflated, at a rate such that two centimeters stretches to four centimeters every minute.

Lets add some starry anthills to the surface, such that most of them are emitting ants, all of whom crawl along the surface towards our hill. Ants crawling at the speed of light, which we will make a quite leisurely pace, say 8 centimeters a minute.

So the little photon ants crawling towards us are hustling along, but the space is expanding so their trips take longer and longer.

For the ants that start a centimeter away, no problem. They arrive before there is much noticable expansion.
For the ants that start 8 cm away, they suffer. The distance between them and their goal is expanding at 8cm/minute at the start, so although they move away from their starting point quickly, they never quite reach the destination.

The ants at 7.9 cm distant make a teensy bit of progress at each step, and as they slowly close the distance, things get easier. All the ants from that hill will eventually make it, although it will take a long time.

So, with this rate of expansion, we can see everything closer than 8cm. Ants that started just short of 8cm will have taken the lifetime of the universe to reach us.

Now, if the expansion accelerates, then the ants from the 7.9cm distant hills can no longer reach us.
As such, the observable part of the universe has shrunk from 8cm radius to 7.9cm or less.

For "small" things like superclusters of galaxies, gravity's pull is plenty strong enough to keep things snug for now. They pull apart a little, but at the same time, keep moving towards each other. If the expansion keeps accelerating then gravity starts losing at smaller and smaller scales... all the way down to star systems. And then eventually electromagnetic forces lose, and rocks get pulled apart... and then nuclear forces lose and atoms get pulled apart. But by then, nobody will care.

[Raapys]

Thanks for the explanation, SJ.

They haven't figured out how the whole 'dark matter' and 'anti-stuff' fits in, have they? And let's say we had a super-fast spaceship and travelled to the edge of the spacetime, do they have any idea what would happen if we tried to move past it?

[Suicide Junkie]

If one of the ants got into a drop of caffeine and started travelling in clear defiance of the speed limits imposed, it would go round and round... there is no edge.

And that's pretty much what we've probably got, in 3D.
As far as it is possible to see, in all directions... you have stuff, more stuff, older stuff, and eventually the microwave background.

Whether it is closed like a balloon shape, or flat or open (saddle-shaped), it is uniform in all directions to the edge of the visible universe. (7.999... cm on the balloon analogy)
So, no evidence for edges.

If it helps, you could think of a closed expanding universe as a game of asteroids... year by year, you keep increasing the resolution of the screen, but it is still a finite size (320x200 way back when, and 1280x1024 nowadays)... there are no edges to fall off of, since the left side is connected to the right side and the top to bottom.
Its not spherical, but rather doughnut shaped, but still finite with no edges, and a decent example.

Also, if your ship can only travel at 1 pixel per second, and you increase the screen rez fast enough, you won't be able to reach objects that happen to be too far away when you start.

[capnq]

If you're finding this discussion interesting, you might also enjoy the most recent Irregular Webcomic (http://www.irregularwebcomic.net/) podcast (http://www.irregularwebcomic.net/podcasts/) (The word "podcast" is a second link.) You can download Episode #4, or read the transcript.

This is one of my favorite Webcomics. The author is a professional astrophysicist, and is quite good at explaining things in layman's terms. Podcast #4 explains why the night sky is black, which turns out to be relevant to this thread.

[Randallw]

I was a tad dissapointed with the latest IWC podcast. It goes for about 9 minutes but after about 30 seconds when he started going on about giant red lights in the sky I thought "Do I really need to listen to this when he will obviously start explaining why the night sky is black". I mean ok he's got a Phd in Physics, what can you expect, but I already know that sort of stuff. When is he going to start explaining M-branes?

What do I know of brane cosmology?. Easy, I wrote half of one of the scenarios http://forum.shrapnelgames.com/images/smilies/biggrin.gif.

Edit: oh and capnq, just if you're interested, I am one of the writers for his new comic project.

[shinigami]

Random thoughts:

I often find it funny how some scientists deride religion because it fails to meet scientific standards but will stand firm on accepted theories that truly can not be proven right or wrong. Hmmm, sounds like faith to me.

If the Big Bang Theory is correct then everything in the universe was created in that instant, albeit in different forms of energy and matter. Therefor, infinite energy is an impossibility because we live in a finite universe. However, if you throw in the infinite universes theory you could get infinite energy by tapping into other universes. Last I heard scientists think that they could accomplish this, but would need an infinite energy source to do so. http://forum.shrapnelgames.com/images/smilies/biggrin.gif

How much is our understanding of physics colored by our own perception? Our perception of "now" is an infinitely small slice of time and by the time our brain receives sensory input the data is already old because travel time for that signal is not instant. Looked at from this point of view we are actually out of step with our environment because we can only perceive the past.

[Renegade 13]

Raapys said:
They haven't figured out how the whole 'dark matter' and 'anti-stuff' fits in, have they?

Nope, they basically have no real idea what dark matter is. An interesting side point about antimatter is that "normal" (baryonic) matter and antimatter should have been created in equal quantity at the big-bang. However, we take a look around and we can't detect any antimatter out there, but there's lots of normal matter. They still haven't figured that one out http://forum.shrapnelgames.com/images/smilies/tongue.gif

[Renegade 13]

Suicide Junkie said:
Just because there is a lot of mass there dosen't mean it is infinite in any way. Where "a lot" is only a handful of stellar masses in many cases.

A handful of solar masses? The central blackhole of the central galaxy of a galactic cluster is estimated to have up to several hundred billion solar masses. It'd take a while to use up that amount of mass/energy.

[Phoenix-D]

shinigami said:
I often find it funny how some scientists deride religion because it fails to meet scientific standards but will stand firm on accepted theories that truly can not be proven right or wrong. Hmmm, sounds like faith to me.




Oh, you can do a lot of proving. Contriving large-scale experiments with astronomy is a *****, but in that respect its not that different from geology or any of the other sciences that involve large-scale processes.

So instead you make models, poke with them, use them to make predictions, and (important step religion leaves out) use them to make predictions. You can test THOSE against reality to see if they match. We can't really test if its possible to exceed C yet, but we can -and have- tested time dilation. Etc.

[Randallw]

I consider the idea of dark matter on par with the Aether. I'm not saying it isn't true but on the one hand they couldn't find how light propogated through space so they invented some invisible substance that filled space, the Aether, and on the other hand they can't figure out where most of the universes weight is so likewise they guess it must be some invisible substance filling space, dark matter.

[Fyron]

shinigami said:
"I often find it funny how some scientists deride religion because it fails to meet scientific standards but will stand firm on accepted theories that truly can not be proven right or wrong. Hmmm, sounds like faith to me."

Let's not derail this discussion...

[narf poit chez BOOM]

I havn't read all of this, but all of you are silly, silly people for trying to figure out how to destroy the Earth.

All the information you need is right here: How to destroy the Earth (http://qntm.org/destroy)

Silly people. You can find anything on the internet.

[capnq]

Randallw said: capnq, just if you're interested, I am one of the writers for his new comic project.

I'll be interested when the first comic appears. I don't really want to watch the creation process, though, so I've ignored that section of the forums.

[capnq]

Renegade 13 said: An interesting side point about antimatter is that "normal" (baryonic) matter and antimatter should have been created in equal quantity at the big-bang. However, we take a look around and we can't detect any antimatter out there, but there's lots of normal matter. They still haven't figured that one out http://forum.shrapnelgames.com/images/smilies/tongue.gif

They do have a theory about that, though. For example, see this lecture (http://abyss.uoregon.edu/~js/ast123/lectures/lec20.html); scroll down to the section labeled "Matter versus Anti-Matter".

[Renegade 13]

Hmmm, that's an interesting link, thanks Capnq! http://forum.shrapnelgames.com/images/smilies/happy.gif So there is a theory for the asymmetry between antimatter and matter, though unproven.

[Suicide Junkie]

Renegade 13 said:

Suicide Junkie said:
Just because there is a lot of mass there dosen't mean it is infinite in any way. Where "a lot" is only a handful of stellar masses in many cases.

A handful of solar masses? The central blackhole of the central galaxy of a galactic cluster is estimated to have up to several hundred billion solar masses. It'd take a while to use up that amount of mass/energy.

Those are pretty rare. And nowhere near infinite.
Lots of holes get formed from stellar deaths, with only 3-tens of stellar masses.


If the Big Bang Theory is correct then everything in the universe was created in that instant, albeit in different forms of energy and matter. Therefor, infinite energy is an impossibility because we live in a finite universe.

How so? Infinite density does not mean infinite energy.

Now, if the universe is infinite in extent and as homogenous as it looks from here, then indeed there would be infinite energy in it.
However you only have access to the observable universe, which is a finite volume of space, with a finite amount of stuff in it.

[Randallw]

capnq said:
I'll be interested when the first comic appears. I don't really want to watch the creation process, though, so I've ignored that section of the forums.



There's an idea. If I'm getting involved perhaps I should actually join the forums.

[shinigami]

Suicide Junkie said:

If the Big Bang Theory is correct then everything in the universe was created in that instant, albeit in different forms of energy and matter. Therefor, infinite energy is an impossibility because we live in a finite universe.

How so? Infinite density does not mean infinite energy.

Now, if the universe is infinite in extent and as homogenous as it looks from here, then indeed there would be infinite energy in it.
However you only have access to the observable universe, which is a finite volume of space, with a finite amount of stuff in it.



I think that was what I was saying, finite universe means finite energy.

For the universe to be infinite wouldn't that mean that somewhere in it energy and matter are being created or added to it? Seeing as physics, as we understand them, can only go back as far as a few milliseconds after the big bang and that time did not exist beforehand then it is possible that the BB is still happening and creating the additional energy for an infinite universe. Very esoteric theory that's hell to wrap my head around! http://forum.shrapnelgames.com/images/smilies/laugh.gif

I think that in man's quest for infinite energy we'll find that it truly doesn't exist (barring extra-dimensional sources) in the strictest sense. However, from our limited point of view (ie, short lifespan compared to the universe,) we'll find plenty of sources that seem to be infinite.
What would you call that, practical infiniteness? http://forum.shrapnelgames.com/images/smilies/wink.gif

Anybody remember the space shuttle tether experiment? (http://www-istp.gsfc.nasa.gov/Education/wtether.html) Compare that with some of Tesla's work and we might have an outstanding source of renewable energy. As for harnessing it....

[Suicide Junkie]

Why would being infinite force there to be addition/subtraction of matter?

It would start out infinite in extent with a finite density and as it stretches, the density goes down.


The conductive tether cutting through the magnetic field of the earth is a handy battery.
But the energy is coming from your orbital speed, which you got using the main engines. Of course, that does make it conveniently easy to deorbit without needing onboard fuel. Excellent for old satellites to ditch themselves once their useful life is up.

[shinigami]

If it is already infinite in extent, how can it be stretching or getting larger? http://forum.shrapnelgames.com/images/smilies/confused.gif Not trying to be a smartass, I just can't follow that line of thought.

Power is constantly being produced in our ionosphere by the collision of the solar wind with our magnetic field. I can see two major problems with tapping into it. First, and most obvious, is just how to do it efficiently. Second, how to keep it from being overloaded and destroyed by solar flares.

I can imagine a sat in orbit trailing a tether. As it orbits it is charging batteries. When the sat reaches a predetermined point in its orbit it beams the stored power to an Earth station as microwaves. Practicality and safety concerns aside, the main question has to be how much power could the thing produce? I have no clue. http://forum.shrapnelgames.com/images/smilies/wink.gif

[Suicide Junkie]

Energy is not being produced in the ionosphere. It just happens to be naturally converted into a convenient form up there. Much like Niagara falls is convenient for hydro plants and sunlight is convenient for plants.
Everything around here except nuclear power comes from the sun. Fission power comes from ancient supernovae.
And both those come from the hydrogen the universe had as far back as we can see.


Re: Stretching infinity
-----------------------
Say you've got a motel with an infinite number of rooms. On Tuesday it happens to be full up with an infinite number of guests, one per room. (This place is quite popular)

Five guys pull up to the front counter, and the owner says "no problem". He simply gets on the intercom and tells everybody to move five doors to the right. The people in room 1 move to room 6, and the people in room one million move to #1000006, and so on.
Now rooms 1 through 5 are empty, and the guys have a place to stay for the night.

Next, a very large frat shows up... they have an infinite number of members, each of which has a unique odd number on their shirt.
"No problem!" says the owner. He gets on the intercom again, and tells everybody to move to the room with double their current room number.
The person in room 1 moves to room 2, the person in room 2 moves to room 4, and the one in room one million moves to room two million. All the odd numbered rooms are now free and everybody still has their own room.
The frat boys then move into all the odd numbered rooms which match their jerseys.

[Renegade 13]

Suicide Junkie said:
Everything around here except nuclear power comes from the sun. Fission power comes from ancient supernovae.
And both those come from the hydrogen the universe had as far back as we can see.

Not quite true. Geothermal energy neither comes from the sun nor nuclear fission; it's generated by the decay of natural radioactive materials like potassium, thorium and uranium. Tidal forces also play a role.

[Suicide Junkie]

nor nuclear fission; it's generated by the decay of natural radioactive materials like potassium, thorium and uranium

That's still supernovae residue, with the same ultimate source.

There is a modest amount of heat available from the formation and gravitational compaction of failed-stars and large planets. But again, that was all there in the potential energy of the starting material.

[Renegade 13]

That is true; I was just pointing out that it's neither directly from the sun, nor from nuclear fission. http://forum.shrapnelgames.com/images/smilies/happy.gif

Sorry, guess I've just been a little arguementative recently http://forum.shrapnelgames.com/images/smilies/tongue.gif

[Jack Simth]

Suicide Junkie said:
Energy is not being produced in the ionosphere. It just happens to be naturally converted into a convenient form up there. Much like Niagara falls is convenient for hydro plants and sunlight is convenient for plants.
Everything around here except nuclear power comes from the sun. Fission power comes from ancient supernovae.
And both those come from the hydrogen the universe had as far back as we can see.


Re: Stretching infinity
-----------------------
Say you've got a motel with an infinite number of rooms. On Tuesday it happens to be full up with an infinite number of guests, one per room. (This place is quite popular)

Five guys pull up to the front counter, and the owner says "no problem". He simply gets on the intercom and tells everybody to move five doors to the right. The people in room 1 move to room 6, and the people in room one million move to #1000006, and so on.
Now rooms 1 through 5 are empty, and the guys have a place to stay for the night.

Next, a very large frat shows up... they have an infinite number of members, each of which has a unique odd number on their shirt.
"No problem!" says the owner. He gets on the intercom again, and tells everybody to move to the room with double their current room number.
The person in room 1 moves to room 2, the person in room 2 moves to room 4, and the one in room one million moves to room two million. All the odd numbered rooms are now free and everybody still has their own room.
The frat boys then move into all the odd numbered rooms which match their jerseys.


Ever heard of orders of infinity? The set of counting numbers is an infinite set, and the set of real numbers is an infinite set, but while you can have a function that uniquely assigns every member of the counting number set to the real number set, you can't do it the other way around. The hotel clerks orders can't be followed - all rooms are full.

[Suicide Junkie]

The frat guys have odd numbers, implying integers. Same as door numbers. There is no problem.
Now, if the frat had used points on a line instead of jersey numbers, then there would be a problem, but they didn't. Fractions would have been fine too.

The whole point of that was to demonstrate stretching an infinite amount of something.
All those people who were neighbours before the move, now have one frat guy between them and are two doors away from their old neighbour. And everybody does fit.

[rdouglass]

If I may jump in...

It doesn't matter whether the frat boys need odd numbered rooms or not; there are an infinite number of them. There are an infinite number of rooms and as long as there is at least 1 person in the hotel, there would not be enough rooms. There is no such thing as infinity + 1. Infinity is infinity. Period. You cannot add to infinity.

At least that's the way it was when I took Calculus and Engineering courses anyways...

[Suicide Junkie]

There is no such thing as infinity +1 because infinity is not a number.

The hotel thing works;
Given that the people follow the owner's instructions in regards to changing rooms, there will never be a room conflict, and everybody will indeed fit.

The person in room 1 moves to room 2. There is nobody in room 2 because that person moved to room 4. Person 2 was able to move into room 4 because *that* person moved into room 8.
The person in room 3 moves to room 6. Person 6 moved to room 12, and 12 to 24.

Everybody leaves their room. And each person is given a unique new room number to move into. One person per room, and nobody left without a room. Therefore everybody fits.

Infinity is funny that way http://forum.shrapnelgames.com/images/smilies/happy.gif
The set of positive, even integers (the original guests in their new rooms) is the same size as the set of all positive numbers (the original guests ... and also the original guests in new rooms plus the frat boys)

[douglas]

There's a whole class of infinities described as "countably infinite" that are all equivalent in size and (among other things) have the property that any two such infinities can be combined to make another infinity that is also countably infinite. The number of rooms in the hotel, the number of current occupants, and the number of frat boys are all countably infinite and can therefore be combined without changing anything. If a fraternity with one member for each irrational number showed up, however, the hotel would be in trouble because that particular set is not countably infinite. No matter what scheme you came up with for assigning people to rooms, you would always have an infinite number still waiting.

Note: A set is countably infinite if and only if it is possible to assign each and every member of the set to a corresponding member of another countably infinite set (the set of all integers is declared to have this property by fiat so you have a base to work with) so that each and every member of both sets has a corresponding member in the other. Put another way, if it's possible to come up with a scheme for labelling each and every item with a different whole number without skipping any numbers, then the set is countably infinite.

On a side note, the set of rational numbers is also countably infinite, but I'll leave figuring out a proof for it to everyone else. I know of one and will post it if enough people ask, but for now I'll leave it as a puzzle.

[PvK]

If there are an infitite number of rooms, it'll probably take you an infinite amount of time to get them to change rooms. Oh NOOOooo...! http://forum.shrapnelgames.com/images/smilies/wink.gif

[douglas]

No no, everyone changes rooms simultaneously and they use special teleporters that can take such things as "double my room number" as the destination so you don't even have to worry about how long it's going to take the people with room numbers with a trillion digits to enter them.

[Suicide Junkie]

Also, the fire code requires an instantaneous FTL intercom.

[narf poit chez BOOM]

Er...No. All you've done is introduced an infinite 'ripple' as people move from room to room. You havn't made more room; you've simply...

...Look, this should explain it. Infinity is not a number. It can, however, be a ratio.

Suppose you have a thirty foot fence and an apple every six inches.

You therefore have 15 epples, thirty feet of fence and 1 apple per 6 inches of fence. 1/6.

Supposing then that an infinite being, for no particular reason, makes the fence inifinitly long and makes sure there's an apple every six inches.

You then have an infinite amount of apples, an infinite amount of fence and a ratio of 1/6 of apples and inches of fence.

Supposing, then, that the infinite being doubled the number of apples, again spacing them evenly. You then have 2/6 or 1/3 of apples and inches.

The ratio of rooms to people is 1/1.

Add in another infinity of people and the ratio of rooms to people is 1/2.

However, as there will *always be more rooms opening up, you've disguised that. However, that 'ripple' is going to go on to infinity - And there will always be one displaced person.

* Unless all this is done in no time at all.

[Suicide Junkie]

Everybody moves at the same time. No ripple, just a quick and simultaneous changing of location.

And yes, practical physical limitations have to be ignored. That's why it is a thought experiment and not a fantastic way to make an infinite amount of profit in just one day. http://forum.shrapnelgames.com/images/smilies/wink.gif

The best part of course, would be that even though the taxman would take an infinite amount of money, you'd still have an infintite amount left (unless the tax rate happens to be 100%).

[narf poit chez BOOM]

The thing you're ignoring is that, while there would always be a room opening up, the room the person is moving into is occupied. The best you could get is to always have someone in transit.

This, of course, may not hold true if action is taken by a being greater than infinite, which would be the only theoretical way to have everyone move at the same time.

[aegisx]

I think Red Dwarf says it all. There was an episode where Dave (who had been in chyo for millions of years) got a message from earth about his bank account. Apparently he has 13 cents or something in there when he left, it now accounts for pretty much all of the money due to the interest. However, he left a lightbulb on in his apartment, so his bill accounts of all of that. I think that is how it went http://forum.shrapnelgames.com/images/smilies/wink.gif

[douglas]

narf poit chez BOOM said:
The thing you're ignoring is that, while there would always be a room opening up, the room the person is moving into is occupied. The best you could get is to always have someone in transit.


That would be true if we were moving people one at a time, but we're not. The hotel's intercom brings the room change announcement to every room simultaneously, and each person moves himself, so all moves are accomplished all at once. When the manager tells everyone to move to the room with double their current room number, person 2 doesn't show up at room 4 and then have to wait for person 4 to leave, person 4 is already out. As is person 8, 16, 32, 64, 128, and so on down the line. Here's how it works at Hotel Infinity:

Step 1: Manager gets on the intercom and tells everyone to move to the room with double his current room number. The intercom relays this message to everyone simultaneously, so all infinity residents are notified in as little time as it takes to say the announcement once.
Step 2: All occupants pack up and move themselves and their belongings into the hall. Every room is now empty.
Step 3: Each occupant steps into the teleporter across the hall and gives "double my previous room number" as the destination. All even numbered rooms are now occupied, but the odd numbered rooms are still empty.

After these steps are completed, in the finite time required for a single person to change rooms, every previous resident has a new room, no one had to be tossed out, and everyone is finished moving into his or her new room. The Hotel contains exactly as many people as it did before, but now every odd numbered room is empty, giving enough room for the entire fraternity of infinite odd-numbered people to move in.

[PvK]

Well if you want infinite money, just become a bank and start charging compound interest...

[narf poit chez BOOM]

Ok, double the room number is an infinitly decreasing fraction of the room ratio...

...Ending up equal to both infinity AND zero?

Dude, I think you just broke the universe.

[Suicide Junkie]

Ratios need to compare two things. Room vs what? ratio.

There is always one person per room. They are all full, and all have exactly one person in each.
That is true both before and after the frat boys get there.