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Originally posted by NSX

I'd like to see it.

I hope it's in Sci-am, because I have about 300 news scientists but only a handful of sci-ams. Give me a day or two and I'll see if I can dig it out.

Originally posted by the GardenGnome

Just being curious. Nothing bad.

Nothing wrong with being curious. In fact, if you were not curious I would find that more "wrong".

 

Sorry if my reply seemed to be harsh or offensive. It was not intended that way.

 

kind regards

Originally posted by fafalone

Everything has meaning.

I see no evidence to support that assertion, or any logical argument that would lead to that conclusion.

 

Maybe I am just dense.

 

kind regards

Originally posted by fafalone

An absense of space and time has meaning, we just don't know exactly what that meaning might be.

 

That just begs the question, IMHO: If you don't know the meaning then how can you claim it has any meaning.

 

kind regards

Originally posted by the GardenGnome

And you have proof to back your statement, theory, hypothesis or whatever you want to call it?

No, and I never claimed to have a proof. I made my statement based on logic. The logic being that to be outside space and time is a meaningless statement because without space and time what have you got? No space and no time. When and where is that precisely?

 

kind regards

Originally posted by fafalone

I apologize also, I was just pissed off because I converted all of it then internet explorer froze when I tried to upload it.. it actually only took 10 minutes to convert

No worries, and thanks for being congenial about it.

 

kind regards

Fafalone,

 

I feel I owe you an apology. I took the time to download the programs and view what you had offered. Had I know how much information was there (200 pages +) I probably would'nt have asked for the format change.

 

Anyways, it was only a small thing. No hard feelings I hope? There's none here (hey, I might need to pick your brains in the future. I don't need to make an enemy of you and certainly don't desire it).

 

As to some of the other comments here. Grow up people. That's the worst kind of bandwaggoning and supposedly intelligent people should have more pride in their behaviour than to think a couple of misplaced words describes someones whole character.

 

If I find a way to convert them and keep their quality I will let you know.

 

kind regards

Originally posted by fafalone

I took the time to find, zip, and post these lectures. If you can't view the format, too bad. Don't read them. Alot of people can view the PS format, especially because of its prominence in science. The PDF conversion makes the quality take a huge hit and there's nothing I can do about that.

What about people who are too lazy to DL Acrobat and view PDFs? Should I convert it to DOC format? Those are both Windows formats, than I have to convert it to Linux. Then the people on BeOS will start complaining.

If you want to read the lectures, download the program. Otherwise, f' off.

:lame:

 

Sheesh, don't lose your rag mate. I made simple request and you immediately call me lazy and now I should f' off. I can see why you're not in public relations.

 

kind regards

Originally posted by fafalone

If you're too lazy to install a program, I'm too lazy to convert them to a pop culture format. Installing GSView would take up far less of your time than converting them would take of mine. (5 minutes vs 10 minutes )

Hang on, I'm lazy because you expect everyone else to download programs to view something you are offering?

 

Now add in all the other 5 minutes that other people without these programs would have to take. 10 minutes of your time v. 5x people's time.

 

kind regards

Originally posted by fafalone

So what would happen if we travelled towards the very edge of the universe and moved faster than it was expanding, and surpassed the "edge"

We'd have to re-write the physics books.

 

kind regards

Originally posted by Glider

So, in a sense, it's filling the vacuum that nature so abhors?

No. There is no "outside" the universe. Not even a vacuum.

 

kind regards

Originally posted by liljohnak

why cant we reach absolute 0?

I read an article sometime back, I think in New Scientist (or maybe Scientific American) that, simply put, said the reason we cannot reach absolute zero is because in trying to remove the last quanta of energy we have to introduce energy into the system which, of course, then replaces the energy we are trying to remove. I'll try and find this article if anyone is that interested (but only if someone specifically request it).

 

kind regards

Originally posted by MrL_JaKiri

I'm going to come back to this topic after I've done some research; I haven't the experience with General that I have with Special.

I'm the same. I know SR pretty well but GR is a little vague to me. I too will be researching this and will let you know if I turn up anything that confirms or refutes my suggestions.

 

kind regards

Originally posted by Soulja

If the universe is expanding, what are we filling up. It cant be space beacuse the universe is space right?

This is always a hard one for people to get to grips with (some are lucky and can make the conceptual leap easily).

 

The Universe is expanding but it does not fill anything up. Hard to imagine as it sounds, but the Universe is "making" space whilst expanding not expanding into a space. :scratch:

 

kind regards

Originally posted by Ragnarak

ps. why can't we delete posts? i accidently quoted this one instead of editing it

 

Its is a pain when you click quote instead of edit. Just use "back page" on your browser.

 

kind regards

Originally posted by fafalone

Cosmic background radiation obviously exists, but exists where there are no particles, so how could both only apply to particles?

I was under the impression that the microwave background is made of particles. These being the photons that mark the time when the Universe became "transparent" to radiation (apprx. t=300,000 years. if my memory serves).

 

kind regards

Originally posted by fafalone

Highly technical, but interesting. Post questions or comments.

 

Alot of people like to argue about the theories based on this stuff, but hopefully this will elucidate how very unlikely it is they know what they're talking about

I'd love to view these but I'm not installing two programs I don't want just to do so. Is there any chance you could convert them to a more familiar format?

 

kind regards

Originally posted by Giles

Um, I could be very badly wrong, but i think the fact that time slows down for the particle as it drops towards the event horizon doesn't actually make a difference to its speed of motion as observed by someone else.

I think you are correct. However, it's speed of motion isn't the critical factor. The critical factor is that it has to take every step on the road to infinite time dilation. No matter how far away from the BH you are, you still have to cover every step on that road to infinity.

 

The important thing to remember is that the lifespan of the BH (I used the 10^60 years figure in my example) is as measured from flat space at infinity above the EH.

 

As you move towards the BH you would have to revise this calculation. You are in a different frame of reference to the BH. As you move closer to the BH your calculation for the lifespan of the BH would be revised down (this is an assumption on my part and one of the things that I would like someone better in the know than myself to verify or correct me on). As you get closer and closer to the BH your revision would make the BH's lifespan shorter and shorter.

 

My reasoning follows:

 

I am in flat space at infinity above the BH. You are in your spaceship between me and the BH. I am looking at the clock on your spacehip (we'll ignore the mechanism for this and the ensuing time delays/shifting of frequency of the signals reaching me/climbing out of a gravity well, it's just time I want to discuss here). Your clock is ticking half as fast a mine. You look back at me at my clock. My clock is ticking twice as fact as yours. (NB. In GR we don't get the same symmetry as SR because GR is accelerated reference frames and these break the symmetry).

 

From my perspective I calculate the BH will exist for 10^60 years. How long do you calculate it will exist, bearing in mind that my calculation was done from a frame of reference that is moving (temporally) twice as fast relative to you?

 

kind regards

Originally posted by MrL_JaKiri

 

See my first point.

 

PS: If this is from reading Hawking, forget everything and read The Elegant Universe, or preferrably The Feynman Lectures on Physics. SH gets quite a few things wrong.

 

Hmm, you didn't quote anything so I'm not entirely sure what you are referring to when you say "see my first point".

 

I can assure you I have read more than 1 book on the subject. I found "Black Holes and Time Warps" not only superior to Hawking but brimming with information.

 

Hey, I just had a thought. I wonder if there are any calculations in the notes at the back that could help solve this problem. I'll get back to you on this with what I turn up.

 

kind regards

Originally posted by MrL_JaKiri

As for stationary observers, you need to use this forumula:

combined recession speed = (a + b) / (1 + ab/c^2)

 

I could be wrong but I think that only applies in Special Relativity when adding uniform velocities. GR is accelerations and non-uniform velocities.

 

kind regards

Originally posted by liljohnak

take this for an idea (idea that i havnt chuged the numbers on but an idea that i thought id share)

 

ok say that you were inside an EH would you even know it?

 

I think not because how much faster can you travel than light speed. so everything will be on a singular clock time. but the only thing is is that you would be stuck inside a glass ball that you can see and know what is happening around you outside but you cant get passed it.

 

I got a ? where could i go to c the numbers they crunched to in theory prove the exsistance of a BH.

 

This is a little programmable applet that show you what the universe would look from various points above, at, or below the EH of a BH.

 

Click here for some fun physics

 

kind regards

Originally posted by Radical Edward

incidentally slinkey... London , Student.... you don't go to Imperial College do you?

No. I wish I could afford to goto any University right now. But I digress...

 

Student on my profile is kind of tongue in cheek in that I study physics (and now math) in my spare time. I use it to indicate that I don't know everything but I am capable of learning.

 

kind regards

Originally posted by Radical Edward

this seems somewhat inconsistent with calculated results. It#'s an interesting sounding paradox (if indeed it is one) I suggest you chug through the maths before really thinking you're right.

I wish I was educated enough to be able to do that. Maybe in 5 years of so.

 

kind regards

Wow, didn't expect such a lot of replies so quickly. Thanks for taking the time to read my ideas.

 

I just want to add some comments that may serve to make people think again on some of their replies.

 

A black hole (BH) is charactersed by it having an event horizon. The event horizon (EH) "marks the spot" where the gravity becomes so extreme that not even light can escape from beyond it.

 

The important thing to remember is that General Relativity (GR) is a classical theory. ie. there is a continual "spectrum" that leads from flat space to the event horizon. This means that any and every point between flat space and the event horizon has an associated gravity and time dilation.

 

At the event horizon time is dilated infinitely. However, classical GR demands that to reach that point of infinite dilation one must cover every point that leads to it (no, I'm not resurrecting Zeno ).

 

You could get to a point just outside the EH that equates to a time dilation of 1sec taking 10^1,000,000 seconds for an observer in flat space.

 

But don't forget, GR demands that I must take every step on the road to infinity. This means that as I move infinitesimally closer to the EH I enter a higher time dilation. The next moment the dilation would be even worse and might calculate to 1 sec taking 10^1,000,000,000 seconds.

 

And again. The next moment the dilation might be 10^1,000,000,000,000.

 

And so on all the way to infinity.

 

One thing that is clear is that the closer you get the the EH the steeper this dilation gradient is. ie. moving 1mm towards the BH when you are far from it doesn't make for much of a change of time dilation. But if you are 1mm above the EH a movement of 1mm would make for a massive change in dilation. In fact, that last 1mm would involve an infinite change in dilation. An infinite amount of time is plenty for a black hole of any size to have evaporated by Hawking Radiation.

 

Anyways, just some more thoughts to ponder.

 

kind regards

Black holes (BH from hereon) are curious objects.

 

The curious thing about them is that if you could watch something falling towards a BH you would never see it cross the event horizon (EH from hereon). For example, if I was watching a clock fall toward a BH, I would notice that it slows down more and more as it gets closer to the EH (it also would get dimmer and dimmer). This will always be the case from any view outside the EH no matter how long you wait. The clock will never be seen to cross the EH. It will slow down and then appear to be frozen (it won't be frozen but will be moving imperceptably).

 

So does the clock ever actually cross the EH of a BH?

 

I say it doesn't.

 

My reasoning for my conclusion:

 

Reason #1:

 

Imagine you are freely falling feet first towards a BH (we'll ignore the "spaghettifying" effects of the increasingly extreme gravity it's just the persepective that I want to deal with). Just below your feet (and closer to the BH than yourself) is a clock also in free fall. ie. as you fall the clock will always be below you and falling at a slightly faster rate because it is experiencing a greater acceleration due to the higher gravity it is experiencing than yourself.

 

As you get closer and closer to the EH you watch the clock. It starts to slow down. This is because as you get closer to the EH the gravity gradient increases. However, you will never see that clock cross the EH as described above. But dig this, not only that, but you are still above the clock. You are still farther away from the EH than the clock. So if you never see the clock cross the EH and you are always farther from the EH than the clock, then you never cross the EH.

 

Reason #2:

 

According to Stephen Hawking a BH isn't entirely black. Due to Heisenberg Uncertainty it is able to lose mass. They "evaporate", and have a temperature which is inversely proportional to their mass. ie. the more massive they are, the less they radiate and the colder they are, and vice versa. Rough figures indicate (1) that for a BH with a mass of 3 to 4 solar masses will take something in the region of 10^60 years to completely evaporate. This is an extraordinarily long time (we don't even know for sure if the Universe will live that long but for my purposes here we'll assume that it will).

 

That 10^60 years calculation is made from the perspective of an outside observer, however, remember when we watch the clock fall towards a black hole we will never see it cross the EH. In effect, we could watch the black hole for 10^60 years and we will never see the clock cross the EH whether we are in stationary orbit above the BH or are falling behind the clock towards the BH.

 

According to GR there is a point above the EH of a BH where the dilation is not only equal to the lifespan of the BH, but greater than the lifespan of the BH. In fact, GR says that there will be a dilation above the EH that is equal to the entire lifespan of the Universe! ie. there is always a point above the EH that would make the black hole evaporate before you get to it's EH.

 

My Conclusion:

Black holes cannot eat anything. In fact, I'm going to stick my neck out (and hope I don't lose my head!) and say that the current picture of black holes is wrong, and if they do exist, then they cannot "eat" and "starve to death".

 

If you can find some holes in my reasoning then please point them out to me.

 

(1) - 3-4 solar masses takes 1060 years to evaporate figures from Stephen Hawking's book "A Brief History of Time".

 

kind regards