WT(Science)F!

[Brant Gaede]

Hard to believe:

http://www.universetoday.com/106725/are-there-more-grains-of-sand-than-stars/

--Brant

[BaalChatzaf]

Perhaps.  If one accepts the Guth expansion hypothesis, there may be parts of the cosmos which are fleeing from us at greater than the speed of light.  The part of the cosmos that is visible to us is about 42 billion ly in diameter.  It is possible that the cosmos is infinite in its size,  but we have no access to that portion which is going away from as at greater than light speed (assuming there is such a portion).  So the question of how many stars is not  completely answerable.

[Brant Gaede]

For me it's the number of atoms in a grain of sand that's hard to get my head around--compared to the number of stars in the universe. Not that that's easy to comprehend either--that is, more atoms than all the stars in the universe?

--Brant

[BaalChatzaf]

10 hours ago, Brant Gaede said:

For me it's the number of atoms in a grain of sand that's hard to get my head around--compared to the number of stars in the universe. Not that that's easy to comprehend either--that is, more atoms than all the stars in the universe?

--Brant

Use exponential notation.

[Brant Gaede]

1 hour ago, BaalChatzaf said:

Use exponential notation.

You have to to do the real science. Then you get your head only around the numbers, however. Taken literally the universe isn't incomprehensibly large for I can get (I imagine) infinite expansion--it might as well be--but I don't get small. Not that small even though it isn't and can't be infinite. Atomic small has to stop with the atom and its bound constituent parts. (And then there's atomic space. In a sense everything is a whole bunch of nothing and in another sense everything is a whole bunch of something for space, as such, doesn't exist except as an idea. My layman's understanding is space is a measure of distance and time of motion--that space-time therefore cannot actually be "bent" for that would be a physicality operating on a pure conceptuality.

--Brant

[BaalChatzaf]

1 hour ago, Brant Gaede said:

You have to to do the real science. Then you get your head only around the numbers, however. Taken literally the universe isn't incomprehensibly large for I can get (I imagine) infinite expansion--it might as well be--but I don't get small. Not that small even though it isn't and can't be infinite. Atomic small has to stop with the atom and its bound constituent parts. (And then there's atomic space. In a sense everything is a whole bunch of nothing and in another sense everything is a whole bunch of something for space, as such, doesn't exist except as an idea. My layman's understanding is space is a measure of distance and time of motion--that space-time therefore cannot actually be "bent" for that would be a physicality operating on a pure conceptuality.

--Brant

Space time curves around masses. This causes a bending of light around massive bodies as has been demonstrated many, many time. Your layman's concept of space-time is just plain Wrong.  The correct operation of the GPS   is a continual reminder that Einstein was right, at least in moderate gravitational fields. General Theory of Relativity probably will break down in very  strong gravitational fields such as exist around black holes. 

[Brant Gaede]

9 hours ago, BaalChatzaf said:

Space time curves around masses. This causes a bending of light around massive bodies as has been demonstrated many, many time. Your layman's concept of space-time is just plain Wrong.  The correct operation of the GPS   is a continual reminder that Einstein was right, at least in moderate gravitational fields. General Theory of Relativity probably will break down in very  strong gravitational fields such as exist around black holes. 

Light yes. Light is something. Light can be bent.

--Brant

I only go as far as my knowledge takes me so, in this case, I cannot follow you to where yours takes you

[BaalChatzaf]

3 hours ago, Brant Gaede said:

Light yes. Light is something. Light can be bent.

--Brant

I only go as far as my knowledge takes me so, in this case, I cannot follow you to where yours takes you

Light follows a geodisic (shortest path).  It is the manifold in which light travels that is curved. You are still used to thinking of space as "flat" in the way that Newton did.  Newton's gravitational theory is incomplete, and it is precisely because Newton got space-time wrong. Einstein got it right or at least more right than Newton.

[Brant Gaede]

Now we have a "manifold" embracing and twisting light?

The problem here, Bob, in your addressing a layman is you are attaching yourself to a tar baby and the more you try to make sense of your position in a way he can understand you get more and more stuck. I'm not, btw, thinking of space as "flat" unless you mean one dimensionally--that is, here is the earth and there is the moon and the "space" between them is 220,000 miles.

That's one way. Do we now add a second? In the second way does "space" acquire substance or is it just another idea? I still see your position as mixing up physicality and conceptuality in trying to make the conceptual physical. Thus "space-time" as being something of a corporeal nature. That is what I do not get. I can understand a lot more as a theorectical construct, but not accept my understanding as objective truth. I think I'm more limited that way than could be corrected by understanding the math behind, say, Einstein's ideas.

--Brant

[BaalChatzaf]

4 hours ago, Brant Gaede said:

Now we have a "manifold" embracing and twisting light?

The problem here, Bob, in your addressing a layman is you are attaching yourself to a tar baby and the more you try to make sense of your position in a way he can understand you get more and more stuck. I'm not, btw, thinking of space as "flat" unless you mean one dimensionally--that is, here is the earth and there is the moon and the "space" between them is 220,000 miles.

That's one way. Do we now add a second? In the second way does "space" acquire substance or is it just another idea? I still see your position as mixing up physicality and conceptuality in trying to make the conceptual physical. Thus "space-time" as being something of a corporeal nature. That is what I do not get. I can understand a lot more as a theorectical construct, but not accept my understanding as objective truth. I think I'm more limited that way than could be corrected by understanding the math behind, say, Einstein's ideas.

--Brant

The real "tar baby" is common sense unregulated and unguided by scientific and mathematical rigor.  Our senses by themselves  leave out most of what is Out There  and distort a goodly portion of what remains. 

I am stating the very, very best physical theory we have.  On the basis of direct experiences we know as much about space and time as a fish knows about water (which is not much).  We have to rely  on idealization, abstraction and inference  supported by the best empirical corroboration we can manage.

General Relativity is the current and all-time champion for talking about space and time.   Quantum Electrodynamics is the current and all time champion for talking about light (i.e. electromagnetic dynamics and radiation).  What is reality REALLY, REALLY, REALLY?   We do not know exactly.  All we have for starters is the crude rendition given to us through our limited and distorting senses.   Common sense  is the worst guide to making correct predictions. 

Aristotle's phusiki  was based on common sense and it is mostly WRONG(!!!!).  

Instead of asking what space-time really, really is  ask for the hypothesis that gives the best corroborated  predictions.  Science is based on experiment, not metaphysical purity.  Metaphysics gives us confusion and The Inquisition.  Experiment based science gives us  our technology (particularly the computer based technology that makes the conversation possible).  Stop asking was Reality REALLY, REALLY is.  The closest you will get is what your eyes and ears tell you.  Unfortunately that does not directly give us what is very  big,  very small,  very fast and very slow.  All our senses gives us is man-scale data which is sufficient for us to survive in this world (barely)  but does not tell us directly what really is going on where our eyes cannot see and our ears cannot hear.  For that we have to really on mathematically derived guesses supported by experiment and measurement.  In short, physical science.  Pure philosophy, in particular metaphysics  gives us confusion and error.

Science did not progress until we unloaded our Aristotelian garbage.