ChatterBank0 min ago
Science And Metaphysics
I read from, 'Sämtliche Werke und Briefe in Vier Bänden', a biography of the Berlin German woman poet; Mascha Kaléko, that in 1952 she sent one of her poems to Albert Einstein, the opening line was; "Time stands still. It is us who are passing away".
Einstein replied: "I think your poem is very beautiful and rich in meaning. It touches upon a deep metaphysical problem that has become relevant through physics".
What do you think he meant by that?
Einstein replied: "I think your poem is very beautiful and rich in meaning. It touches upon a deep metaphysical problem that has become relevant through physics".
What do you think he meant by that?
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Jim360
I agree gravity can have no effect on light at all because it has no mass. The observed effect of gravity on the path of light thus has to be an indirect one which Einstein and others since believe is due to the ability of gravity to create a curvature of spacetime, the medium through which the light is passing.
I haven't read much about 'gravitational hydrodynamics' but the name might suggest that it attributes fluid-like and not 'fabric'-like characteristics to what spacetime might actually be like.
Imagine we are sitting in an invisible waterfall of spacetime plummeting down towards the earth's centre of mass. Anything not secured against it joins the spacetime torrent such as an apple falling down on Newton's head!
I agree gravity can have no effect on light at all because it has no mass. The observed effect of gravity on the path of light thus has to be an indirect one which Einstein and others since believe is due to the ability of gravity to create a curvature of spacetime, the medium through which the light is passing.
I haven't read much about 'gravitational hydrodynamics' but the name might suggest that it attributes fluid-like and not 'fabric'-like characteristics to what spacetime might actually be like.
Imagine we are sitting in an invisible waterfall of spacetime plummeting down towards the earth's centre of mass. Anything not secured against it joins the spacetime torrent such as an apple falling down on Newton's head!
Dear Colmc54,
I'm not sure whether your answer was addressed to jim or me.
But I for one, think your waterfall analogy (quite good) is predicated by the acceptance of the curvature of space-time. Has the latter been proven in any way i wonder.
I am a great lover of maths (well traditional calculus & algebra etc) but wonder if any of the cosmological maths include elements like the square root of -1 for example. O.K. we can play with it even in arithmetic as well as maths but it has no meaning in the real world or universe does it, I wonder. And do intergrational terms have defined limits and if so, I wonder how these limits are set.
Please note, a simple biochemist like me has not posed questions that need answers as I do not wish to interfere with inter-physical debates. Please ignore or comment as you wish.
I will certainly understand ignoral (well justified) but cannot guarantee understanding comments/replies -lol.
Very Sincere Welcome to the Thread C,
Deepest Respects,
SIQ.
P.S. Happy New Year to All, If We Share the Same Clocks - Mine Says 09.37 p.m. Dec. 2013 But It Ran Out of Energy - Must buy a new battery!
I'm not sure whether your answer was addressed to jim or me.
But I for one, think your waterfall analogy (quite good) is predicated by the acceptance of the curvature of space-time. Has the latter been proven in any way i wonder.
I am a great lover of maths (well traditional calculus & algebra etc) but wonder if any of the cosmological maths include elements like the square root of -1 for example. O.K. we can play with it even in arithmetic as well as maths but it has no meaning in the real world or universe does it, I wonder. And do intergrational terms have defined limits and if so, I wonder how these limits are set.
Please note, a simple biochemist like me has not posed questions that need answers as I do not wish to interfere with inter-physical debates. Please ignore or comment as you wish.
I will certainly understand ignoral (well justified) but cannot guarantee understanding comments/replies -lol.
Very Sincere Welcome to the Thread C,
Deepest Respects,
SIQ.
P.S. Happy New Year to All, If We Share the Same Clocks - Mine Says 09.37 p.m. Dec. 2013 But It Ran Out of Energy - Must buy a new battery!
In Euclidean geometry, a straight line is 'the shortest distance between two points', if a photon is deflected around a gravitational force it must take a longer duration of time to arrive as it is travelling a longer distance, -so space affects time - and (returning to the OP) if spacetime can be slowed down, what (maybe hypothetical) circumstances would be required for time to 'stand still'?
^ This post is definitely alcohol-fuelled, and Happy New Year to all!
^ This post is definitely alcohol-fuelled, and Happy New Year to all!
The entire point of General Relativity is that Euclidean Geometry doesn't work in the Universe as a whole, so... in fact light always travels the shortest possible distance between two points and takes the least possible time to make that journey. To make time "stand still" is a bit of a misnomer, really, since it depends on who is doing the measuring. Watching someone move near a Black Hole you might see them stuck on the event horizion in a stationary position, as if for them time has stood still. But the willing volunteer who got so close to the Black Hole wouldn't notice time standing still (mainly because he'd be dead, but also because one of the key ideas of Relativity is that you shouldn't be able to tell whether or not you are the one who is moving).
Jim I think you are in need of a solipsism warning. Most rational people believe that the universe was getting on fine for billions of years before we humans came along and started observing stuff.
What E. so politely observed at the start of this thread was that such considerations are at the far outposts of human understanding, a place where neither philosophers or natural philosophers, as scientists used to be called, can presume to make territorial claims.
E. said that general relativity was inspired by the reported testimony of a man who fell off a roof and said that during his fall he felt weightless.
I agree with the great professor that new insights can come from philosophy, religion, and even people falling off roofs.
Natural philosophy requires us to listen and learn from everything and everyone. I humbly suggest that E. would concur.
What E. so politely observed at the start of this thread was that such considerations are at the far outposts of human understanding, a place where neither philosophers or natural philosophers, as scientists used to be called, can presume to make territorial claims.
E. said that general relativity was inspired by the reported testimony of a man who fell off a roof and said that during his fall he felt weightless.
I agree with the great professor that new insights can come from philosophy, religion, and even people falling off roofs.
Natural philosophy requires us to listen and learn from everything and everyone. I humbly suggest that E. would concur.
Dear Colmc54,
Your post to jim was very interesting.
Yup, anyone who wishes to enighten themselves or mankind should be open to the experiences/views of all others (and I would add the behaviour of materials around us - as we perceive it).
If E. really did conceive anything fundamental from the man falling off the roof then that was a great leap of genius! No pun intended.
Sitting here I "feel" weightless, until I start standing up. Similarly I feel lighter going downstairs than I do going up. All this is merely my perception as my mass and the g-force exerted on me is constant.
Did E. really need a man falling off a roof to bring home to him what is obvious to a post-Newtonian dope like me?
I think the roof-faller, like Newton's apple, are most likely to arise as simple illustrations by the great men to transmit the the concept of a fundamental new discovery to the masses. O.K. let's avoid the basis of the "apple" story.
Many knowledgeable people are also great teachers
with Richard P. Feynman, as you well know, being the classic example.
Sorry to interrupt, over to you jim.
With great respect Colmc,
SIQ.
Your post to jim was very interesting.
Yup, anyone who wishes to enighten themselves or mankind should be open to the experiences/views of all others (and I would add the behaviour of materials around us - as we perceive it).
If E. really did conceive anything fundamental from the man falling off the roof then that was a great leap of genius! No pun intended.
Sitting here I "feel" weightless, until I start standing up. Similarly I feel lighter going downstairs than I do going up. All this is merely my perception as my mass and the g-force exerted on me is constant.
Did E. really need a man falling off a roof to bring home to him what is obvious to a post-Newtonian dope like me?
I think the roof-faller, like Newton's apple, are most likely to arise as simple illustrations by the great men to transmit the the concept of a fundamental new discovery to the masses. O.K. let's avoid the basis of the "apple" story.
Many knowledgeable people are also great teachers
with Richard P. Feynman, as you well know, being the classic example.
Sorry to interrupt, over to you jim.
With great respect Colmc,
SIQ.
I think ideas can spring from unexpected sources, if E. said it came from the falling man, that's where it came from. Claiming no such profoundity here, but a 4 year old girl once informed me; "We close the blinds at night to keep the dark out". Before saying anything I thought about it; what is dark? is it purely the lack of light, or a phenomenon in itself? does it enter the room through the window? is the room lighter by closing the blinds? if I light one candle (1 candle power) in a large closed room, is there less light than 1cp in a small closed room? If the blinds were not closed and I stood outside I could observe the candle within, so photons must be being released from the room through the window, etc. etc. It didn't lead to a Nobel prize, but I wouldn't have thought about such things without her statement, to which, like E. I said was "very beautiful".
Comments please.
Comments please.
P.S. Nope Colmc your opening statement re the universe and mankind's "effect" is plumb wrong. We (mankind) are part of the universe thro' an apparent contradiction of the laws of thermodynamics although we are a mere blip in the entropy law by stealing energy from the sun.
As such, we are a mere transient universal event and our primitive "understanding" is probably fundamentally wrong - it's perception only.
That our existence and observations could materially effect the universe is not on. To proceed along those lines maybe get's us into the concept of "universal conciousness" with which I have a certain sympathy although don't tell Khandro, lol.
You can forget Heisenberg on this one.
Regards,
SIQ.
As such, we are a mere transient universal event and our primitive "understanding" is probably fundamentally wrong - it's perception only.
That our existence and observations could materially effect the universe is not on. To proceed along those lines maybe get's us into the concept of "universal conciousness" with which I have a certain sympathy although don't tell Khandro, lol.
You can forget Heisenberg on this one.
Regards,
SIQ.
//f I light one candle (1 candle power) in a large closed room, is there less light than 1cp in a small closed room?//
You're being imprecise with your use of the word light which leads to the confusion.
There is light and density of light
If you think of it as heat it becomes clearer
If I burn a log in a small room the same heat is generated as if I burn a log in the middle of the Royal Albert hall
But because the volume is smaller the temperature goes up more
Similarly you candel generates the same amount of light in a small room but the density of that light hitting the walls is greater and so the reflected light is more appreciable and it is the reflected light that allows us to see things other than the flame
You're being imprecise with your use of the word light which leads to the confusion.
There is light and density of light
If you think of it as heat it becomes clearer
If I burn a log in a small room the same heat is generated as if I burn a log in the middle of the Royal Albert hall
But because the volume is smaller the temperature goes up more
Similarly you candel generates the same amount of light in a small room but the density of that light hitting the walls is greater and so the reflected light is more appreciable and it is the reflected light that allows us to see things other than the flame
Dear jim,
Well said!
I thought you would ignore that unjustified patronising term solipsism.
You are one of very few who are in no need of advice on what, I think means something like self-centered thinking. I' may be wrong in my remembering from student days when I had to ask my chemistry tutor what it meant -he was referrring to a colleague's views over a tea-time get-together.
Whenever you have deigned to answer my own or other's questions/comments you have shown great modesty saying approx: "I'll get back to you after thinking or reference to your maths etc." At no stage have you or I got involved with the importance of the "self" as reality or concepts.
Typical me I'll now have to check on the definition after shooting from the mouth! If I'm wrong, apologies to all.
Regards,
SIQ.
Well said!
I thought you would ignore that unjustified patronising term solipsism.
You are one of very few who are in no need of advice on what, I think means something like self-centered thinking. I' may be wrong in my remembering from student days when I had to ask my chemistry tutor what it meant -he was referrring to a colleague's views over a tea-time get-together.
Whenever you have deigned to answer my own or other's questions/comments you have shown great modesty saying approx: "I'll get back to you after thinking or reference to your maths etc." At no stage have you or I got involved with the importance of the "self" as reality or concepts.
Typical me I'll now have to check on the definition after shooting from the mouth! If I'm wrong, apologies to all.
Regards,
SIQ.
Dear Khandro,
Why not just accept Jake's excellent analogy?
The candel-power (I don't know the SI unit) is a correct definition under standard temperature and pressure.
Of course "light" is an energy fact but as such can be changed to heat or (dare I say mass - lol).
You are referring to the old paraffin candle now. Sure, its' energy is emitted as light/heat within our limited perception of the EM spectrum. Try snuffing it out with you fingers and the potential energy from the gas/oxygen reaction will burn you but not with light - oh no don't do that, please.
Many thanks for your example of curtains "keeping out the dark". I'll have to think about that but probably remain pondering forever. But very good provocative story. Well done K.
Kindest Regards,
SIQ.
Why not just accept Jake's excellent analogy?
The candel-power (I don't know the SI unit) is a correct definition under standard temperature and pressure.
Of course "light" is an energy fact but as such can be changed to heat or (dare I say mass - lol).
You are referring to the old paraffin candle now. Sure, its' energy is emitted as light/heat within our limited perception of the EM spectrum. Try snuffing it out with you fingers and the potential energy from the gas/oxygen reaction will burn you but not with light - oh no don't do that, please.
Many thanks for your example of curtains "keeping out the dark". I'll have to think about that but probably remain pondering forever. But very good provocative story. Well done K.
Kindest Regards,
SIQ.
Sorry no offence intended. I didn't mean the 'self-obsessed' meaning of solipsim but the philisophical idea that everything real in our universe exists only in the mind alone.
Wiki-
"Solipsism (i/ˈsɒlɨpsɪzəm/; from Latin solus, meaning "alone", and ipse, meaning "self") is the philosophical idea that only one's own mind is sure to exist. As an epistemological position, solipsism holds that knowledge of anything outside one's own mind is unsure. The external world and other minds cannot be known, and might not exist outside the mind. As a metaphysical position, solipsism goes further to the conclusion that the world and other minds do not exist. As such it is the only epistemological position that, by its own postulate, is both irrefutable and yet indefensible in the same manner."
What kind of a mind would conjure up a universe that appears to have existed for billions of years before the human mind that concieved it it? I guess that was the point I was trying for but maybe 'anthropocentric' would have been more suited.
Wiki-
"Solipsism (i/ˈsɒlɨpsɪzəm/; from Latin solus, meaning "alone", and ipse, meaning "self") is the philosophical idea that only one's own mind is sure to exist. As an epistemological position, solipsism holds that knowledge of anything outside one's own mind is unsure. The external world and other minds cannot be known, and might not exist outside the mind. As a metaphysical position, solipsism goes further to the conclusion that the world and other minds do not exist. As such it is the only epistemological position that, by its own postulate, is both irrefutable and yet indefensible in the same manner."
What kind of a mind would conjure up a universe that appears to have existed for billions of years before the human mind that concieved it it? I guess that was the point I was trying for but maybe 'anthropocentric' would have been more suited.
When accumulated knowledge begins to provide the luxury of time for contemplation it becomes quite easy to forget why we came this way to begin with . . . for the benefits such knowledge contributes to sustaining and promoting the existence of those with the ability to do so. It might be argued that in time, time has become something some of us apparently have too much of.
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