Ask a physicist anything. (5)

Here's something interesting:

BBC News - Spinning black holes 'twist light'

http://news.bbc.co.uk/2/hi/science/nature/8091271.stm

mzungu said:

That I know but an element that is comprised of atoms with God knows how many protons, neutrons, and electrons cannot exist for longer than a few trillionths of a second. It would be extremely unstable and radioactive. So how does it reach singularity if due to its short lifespan releases all its energy

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Gravity is the cause of, and solution to, all of life's problems The cause of instability in heavy nuclei is due to the fact that an extra neutron doesn't contribute that much more to the stability of the nucleus.

Imagine you're stacking boxes. You start with a single box. Naturally, that's as stable as stable can be. You add another box on top, slightly off centre - it's slightly unstable, but still pretty good. You add a third box, so you have a sort of inverted triangle of three stacked boxes, and voilà, your three boxes are more stable than the two. Keep doing this: each new box goes on the left and works its way right, then going up a level.

This is kinda what happens with nuclei. Each new box offsets the whole structure's stability somewhat, and when you get to high levels of boxes, a single box can destabilise it by quite a lot - unless it is itself acting as a counterweight and making the whole thing tentatively stable.

So, that's what happens normally, that's why excessively heavy nuclei spit out excess nucleons left right and centre. In reality, nucleons stick together because of the residual strong nuclear force (i.e., the force holding a proton's quarks together also causes quarks from different nucleons to pull together - hence why nucleons stay together).

So, usually, extra nucleons are repelled by various forces, and attracted by the residual strong nuclear force. Excess nucleons just aren't held on tightly enough, so get spit out, taking some nucleons with them - i.e., spontaneous alpha decay - or even splitting the nucleus in two - i.e., nuclear fission.

But what if there was a force much much greater than the residual strong force to hold them together? In the case of a black hole, gravity overcomes any internal or external force that might try to push them apart. Two protons, despite being repelled by their similar charges, are forced into a fatal hug by gravity.

mzungu said:

Can you calculate the atoms of such an element?

Do some number crunching for us puhleeeezzzzzz

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I don't know which element you mean :o

Assyrian said:

Or how large would an atom have to be for the radius of the nucleus to equal its Schwarzschild radius? Would the size of the protons and neutrons be compressed by their gravity too?

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Well, the Shwarzschild radius is proportional to the mass of the object, and atoms are so very light that their radius is so very small that you'd probably never squeeze a single atom into a black hole - according to some theories in quantum mechanics, there is a fundamental graininess to the universe, the plank scale, beyond which you can't get any smaller. It may just be that atoms are simply too light to become black holes.

mzungu said:

Here's something interesting:

BBC News - Spinning black holes 'twist light'

BBC NEWS | Science & Environment | Giant black holes just got bigger

Click to expand...

Urgh, spinning black holes. They gave me such a headache at uni, but I found out they have two shells of photons orbiting just outside the event horizon, swirling in different directions - with the black hole, and against it. Quite creepy.

Wiccan_Child said:

Gravity is the cause of, and solution to, all of life's problems The cause of instability in heavy nuclei is due to the fact that an extra neutron doesn't contribute that much more to the stability of the nucleus.

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This leads me to believe that it is not Gravity that directly effects all matter but the curvature of spacetime that effects matter; Otherwise how can we explain mass-less particles not being able to escape a black hole?

Come to think of it this is why we cannot escape our 3 dimensions. We are forever doomed to the embrace of our limited reality which is influenced and encased in 3 dimensions. However as for the 4th dimension? Well since we cannot travel at relativistic speeds; Then our only chance of influencing time would be through the effects of gravity but I seriously doubt if we can survive anything coming close to a time dilating gravitational field.

Hmmmm!!!!

Can you get me a funded Phd position?

Wiccan, can you recommend any good recent pop-sci book on cosmology, quantum stuff and/or string theory? Gleaning bits and bobs from the internets just doesn't have the same atmosphere sitting down with a good book does. (Is Hawking's latest any good if I'm interested in the physics, not the God issue?)

I recommend the Book by Brian Greene: The Elegant Universe. (it is slightly old but excellent reading). The elegant universe: superstrings, hidden dimensions, and the quest for the ultimate theory [Book]

Also you can watch the documentary: The Elegant Universe | Watch Free Documentary Online

I remember seeing a video about a water that appears to break the laws of gravity, though I can't remember what the video is called exactly, so care to explain?

Also how does the chemical gold give off a red color when individually separate from each other?

mzungu said:

I recommend the Book by Brian Greene: The Elegant Universe. (it is slightly old but excellent reading). The elegant universe: superstrings, hidden dimensions, and the quest for the ultimate theory [Book]

Also you can watch the documentary: The Elegant Universe | Watch Free Documentary Online

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I had watch that video in science class, it had me thinking for a couple of days trying to think of a solution of the problem.

Naraoia said:

Wiccan, can you recommend any good recent pop-sci book on cosmology, quantum stuff and/or string theory? Gleaning bits and bobs from the internets just doesn't have the same atmosphere sitting down with a good book does. (Is Hawking's latest any good if I'm interested in the physics, not the God issue?)

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I haven't read his latest book, but apparently the whole God thing is a single sentence at the end of the book that doesn't say what the media claimed it to say. His previous two books (A Brief History of Time, and The Universe in a Nutshell) are very good, and give a good, conceptual understanding of modern physics without overloading you with chunky maths. They're both still relevant and accessible, so they're my recommendations

mzungu said:

I recommend the Book by Brian Greene: The Elegant Universe. (it is slightly old but excellent reading). The elegant universe: superstrings, hidden dimensions, and the quest for the ultimate theory [Book]

Click to expand...

Maybe I'm just a really bad reader, but all I got from that book is that no one even knows what string theory is :o Perhaps it's the translator's fault.

Also you can watch the documentary: The Elegant Universe | Watch Free Documentary Online

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Oooh, shiny! I'll go start on that tonight!

Wiccan_Child said:

I haven't read his latest book, but apparently the whole God thing is a single sentence at the end of the book that doesn't say what the media claimed it to say.

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Once again, my cynicism about the media finds justification

His previous two books (A Brief History of Time, and The Universe in a Nutshell) are very good, and give a good, conceptual understanding of modern physics without overloading you with chunky maths. They're both still relevant and accessible, so they're my recommendations

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I'll give The Universe in a Nutshell another go. Last time I read it, my brain started smouldering halfway through. I'm starting to think it's time to just accept that feeling, because physics doesn't look like it's going to get any less mind-boggling

I've got both (A Brief History of Time, and The Universe in a Nutshell) on audio books, enjoy them & have listened to them a few times. Also "A Briefer History of Time" & "A Short History Of Nearly Everything"

Maxwell511 said:

That was/is Godel's position or at least his musing to his friend Einstein. I believe that it relates to his theorems on logical systems about consistency and completeness.

I sort of agree with Godel in that his theorems can be applied to reality, however I disagree on the position. My personal view is that fundamental physics is about finding the "axioms" of the universe and I believe that these axioms will be consistent. However due to Godel's theorem they will not lead to completeness i.e. a theory of everything is impossible or reductionism does not work. For example I do not think that biological theories can be theoretically derived from a complete knowledge of the laws of nature that make up lifeforms.

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I'm not sure I follow. Godel's incompleteness theorems referred to first order logical languages being unable to completely and consistently symbolise basic arithmetic - this doesn't mean the universe at large doesn't operate according laws and rules than can be described by a single grand unified theory, and I really don't see what it has to do with reductionism

Why can't we, in principle, derive biological theories from their biochemical, chemical, or even physical underpinnings?

Maxwell511 said:

Your position seem to be that we can get completeness by abandoning consistency. So GR and QM are not consistent therefore we can (for example) reduce biological theories to physics.

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Err... no. The inconsistency between GR and QM means that either one, the other, or both, are false. Physicists, myself included, tend to err on the side of QM; unforuntately for Einstein, GR is not as good as QM.

Maxwell511 said:

What is a universe?

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A thing containing things that behave according to mathematically describable laws.

Maxwell511 said:

What is a universe?

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I’m wondering.. Where is it.. inside of us… or outside.


If it exists outside of us.. we have a problem with time.. because the entire universe exists in our past.

Is something that always exists in our past real or not.. ?

Some of the stars may no longer exist.. all we see are memories.

What is outside us doesn’t seem to belong in our time… it is more disconnected from us than the beginnings of man. It is a history of what was.

The image of the universe we have in our minds exists in the present.. so does that make it realer than the universe that may.. or may not.. exist outside us.. ?

Which is the real universe.. the one we perceive.. or the history.. ?

Is the universe a mental construct.. something that exists at the very limit of our perception..?

Then again.. is the universe a platform for emerging consciousness . like a theatre.. a stage,, for living things to create their own dramas.. and unique stories.. a place for adventures.. a place of mystery.. something that invites exploration.

Is it a place where perceptions.. feelings.. memories.. and dreams.. give the universe an additional imaginary dimension.. thereby putting mind at its centre.. ?

If the universe had an imaginary dimension.. would that explain the “problem of consciousness”.. ?

Our experience tells us the mental and physical are intimately linked.. but how can we account for this in physics..?

Are we caught up in some kind of paradox..?

Could we.. perhaps.. use imaginary terms to resolve it....?

“It is about time, that both mathematical and scientific analysis give more importance and meaning to all imaginary terms. In multitudes of important derivations, in both maths and physics, we find imaginary roots and solutions literally dropped off or disregarded, just because they are not real. Disregarding imaginary components in the physical world has serious consequences and is what makes things look to behave weird or showing overunity. If one does not fully understand that the imaginary components EXIST as much as the real components, he may be easily tricked, and could never for example, explain why a seemingly genuine overunity device can never be made self running.

The implications are rather obvious, an imaginary space-time dimension has to be defined along with the four real space-time dimensions to fully represent all physics parameters. This shall upgrade all physics units into a set of space-time dimensions, one with real and the other with imaginary, resulting into at least one complex 4 dimension space time. This requires no major change in physics, but from thereoff, ALL quantities have to be assumed to be complex values, that is, have BOTH REAL & IMAGINARY COMPONENTS of space-time.”

http://www.blazelabs.com/f-p-hole.asp

Start wrapping your iphones with lead foil cause its coming!

Biggest Solar Flares in 4 Years Heading Toward Earth - PCWorld

http://www.nasa.gov/topics/solarsystem/features/flare_surprise.html

AllOrNothing said:

I’m wondering.. Where is it.. inside of us… or outside.


If it exists outside of us.. we have a problem with time.. because the entire universe exists in our past.

Is something that always exists in our past real or not.. ?

Some of the stars may no longer exist.. all we see are memories.

What is outside us doesn’t seem to belong in our time… it is more disconnected from us than the beginnings of man. It is a history of what was.

The image of the universe we have in our minds exists in the present.. so does that make it realer than the universe that may.. or may not.. exist outside us.. ?

Which is the real universe.. the one we perceive.. or the history.. ?

Is the universe a mental construct.. something that exists at the very limit of our perception..?

Then again.. is the universe a platform for emerging consciousness . like a theatre.. a stage,, for living things to create their own dramas.. and unique stories.. a place for adventures.. a place of mystery.. something that invites exploration.

Is it a place where perceptions.. feelings.. memories.. and dreams.. give the universe an additional imaginary dimension.. thereby putting mind at its centre.. ?

If the universe had an imaginary dimension.. would that explain the “problem of consciousness”.. ?

Our experience tells us the mental and physical are intimately linked.. but how can we account for this in physics..?

Are we caught up in some kind of paradox..?

Could we.. perhaps.. use imaginary terms to resolve it....?

“It is about time, that both mathematical and scientific analysis give more importance and meaning to all imaginary terms. In multitudes of important derivations, in both maths and physics, we find imaginary roots and solutions literally dropped off or disregarded, just because they are not real. Disregarding imaginary components in the physical world has serious consequences and is what makes things look to behave weird or showing overunity. If one does not fully understand that the imaginary components EXIST as much as the real components, he may be easily tricked, and could never for example, explain why a seemingly genuine overunity device can never be made self running.

The implications are rather obvious, an imaginary space-time dimension has to be defined along with the four real space-time dimensions to fully represent all physics parameters. This shall upgrade all physics units into a set of space-time dimensions, one with real and the other with imaginary, resulting into at least one complex 4 dimension space time. This requires no major change in physics, but from thereoff, ALL quantities have to be assumed to be complex values, that is, have BOTH REAL & IMAGINARY COMPONENTS of space-time.”

[URL]http://www.blazelabs.com/f-p-hole.asp[/URL]

Click to expand...

You do know, don't you, that complex vectors with "real" and "imaginary" components have been used by scientists for many decades? Of course the terms "real" and "imaginary" are used in a special sense in mathematics, just as the term "rational number" means numbers that can be reduced to a ratio of integers. It does not mean that a number that is not "rational" is a creationist number.

If you are really interested, you might want to check out, "quaternions" and "Clifford algebras". It is really fascinating stuff!

Wiccan_Child said:

A thing containing things that behave according to mathematically describable laws.

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That's so going in my signature

ETA: OK, it's not. Stupid character limit

Wiccan_Child said:

A thing containing things that behave according to mathematically describable laws.

Click to expand...