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Author Topic: Does ' NOW ' exist ?  (Read 17083 times)

Offline DrN

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Re: Does ' NOW ' exist ?
« Reply #25 on: 16/02/2005 19:07:35 »
my head is starting to spin! how can positive mass be attracted to negative mass when it is in fact being repelled by the positive mass? Like the donkey and his carrot on a stick, always trying to reach it but constantly pushing it away. is negative mass antimatter? or is that something different entirely?
 

Offline MayoFlyFarmer

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Re: Does ' NOW ' exist ?
« Reply #26 on: 16/02/2005 20:34:20 »
is your head spinning faster than the speed of light?

Are YOUR mice nude? ;)
 

Offline neilep

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Re: Does ' NOW ' exist ?
« Reply #27 on: 16/02/2005 20:49:52 »
Isn't negative mass what a bunch of depressed catholics get up to ?

'Men are the same as women...just inside out !'
 

Offline realityengineer

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Re: Does ' NOW ' exist ?
« Reply #28 on: 16/02/2005 22:26:10 »
Where did you hear about the positive negative mass interactions?
 

Offline DrN

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Re: Does ' NOW ' exist ?
« Reply #29 on: 16/02/2005 22:29:18 »
quote:
is your head spinning faster than the speed of light?


lol!:D

not sure .... if it were would I be thinking thoughts I already thought of .... or ones I hadn't yet got round to thinking about?

 

Offline gsmollin

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Re: Does ' NOW ' exist ?
« Reply #30 on: 17/02/2005 15:19:48 »
quote:
Originally posted by realityengineer

Where did you hear about the positive negative mass interactions?



I got it backwards. The negative mass has the anti-gravity, and repels the positive mass. But the positive mass has gravity, and attracts the negative mass. This pair would zoom off through the universe.

I read this in a book, "The New Physics", published by Cambridge University Press. It was in a chapter "The Renaissance of General Relativity", written by Clifford Will.

The negative mass concept comes about because of the negative sign of gravitational binding energy. The mass of a star or other compact object is always less than the mass of its constituent particles, if they were all placed at inifinity. As the star forms from the nebula, it must radiate its gravitational binding energy, and when it is done, it has less mass than the original nebula. The difference is the gravitational binding energy. Now it was postulated that if a compact mass shrank enough, it could lose enough gravitational binding energy to become a negative mass. This was debated for years, and a theorem of GR was proposed to prohibit this. It was proved by some mathematicians, and subsequently by GR theorists, using another method. So GR now prohibits negative mass, via the positive mass theorem.
« Last Edit: 18/02/2005 00:21:32 by gsmollin »
 

Offline realityengineer

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Re: Does ' NOW ' exist ?
« Reply #31 on: 17/02/2005 19:57:07 »
so your saying that if negative mass existed, it would repel positive mass, but due to GR it doen't exist...
 

Offline gsmollin

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Re: Does ' NOW ' exist ?
« Reply #32 on: 18/02/2005 00:24:05 »
Yes, positive mass curves space towards it, and negative mass curves it away. However, much like the square root of -1, negative mass is not real.
 

Offline realityengineer

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Re: Does ' NOW ' exist ?
« Reply #33 on: 18/02/2005 03:28:05 »
doesn't exist in three dimensional space, got it.
 

Offline chimera

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Re: Does ' NOW ' exist ?
« Reply #34 on: 21/02/2005 19:16:23 »
quote:
Originally posted by gsmollin

Time is a very peculiar dimension, is it not?
Einstein formalized this in the special theory of relativity. His four-dimensional world space is defined as x, y, z, and -ict.



But I wonder who ever said time has to be a 'whole' dimension? I can imagine reality having 'fractal' dimensions, meaning 1+1+1 plus time not equalling four, but maybe pi, for all we know. Maybe that's why pi is pi, because this universe is not truly 4 dimensional, but three-something-ish. It's sort of halfway between here and there, say.  Remember that in string theory they have 7 dimensions just 'rolled up', too.

Dunno, makes some weird sense, somehow. Systems with 'fixed' numbers generally don't work. There needs to be some 'tension' in the system, it seems. Some kind of imbalance.

:)
 

Offline MayoFlyFarmer

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Re: Does ' NOW ' exist ?
« Reply #35 on: 22/02/2005 05:07:37 »
oooooo.......   fun

Are YOUR mice nude? ;)
 

Offline chimera

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Re: Does ' NOW ' exist ?
« Reply #36 on: 22/02/2005 14:40:25 »
quote:
Originally posted by MayoFlyFarmer



[1] oooooo.......   fun

[2] Are YOUR mice nude? ;)



[1] Oh, it gets much weirder than that. Remember electromagnetics does not only work in three dimensions, but also in one (1). This would seem a bit useless, but it means that theoretically you'd be allowed to switch single dimensions with others without a glitch. So if you had a shape like an icositetrahedron (24-cell, hyperdiamond) which is purely 4-dimensional, you could have a 'particle space' that could do the switcherola with 24 sides (8 by 3 model, known from quark fame) giving all kinds of hints of 7 dimensions 'rolled up', but failing to see it's actually 3 times 7 dimensions that you don't see all of the time. All this with slightly above industry-strength 'refresh rates', naturally.

It would also explain why some particle phenomena seem to happen 'elsewhere'. They do, in a sense.

The imperfect continuous translation from a 4 dimensional shape crammed into 3 leads to a surplus that we experience as time.

Sort of, but I think it's pretty close (seriously)

[2]Ofcourse, or I'd have a few pretty confused-looking snakes when I feed them. (just kidding).

:)
« Last Edit: 22/02/2005 14:41:24 by chimera »
 

Offline chimera

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Re: Does ' NOW ' exist ?
« Reply #37 on: 24/02/2005 12:15:06 »
Now the polite thing to ask would be:

- have you taken your medicine recently? (don't have any, never worry)
or alternatively:
- do you have any supportive evidence for such far-fetched, apparent nonsense? (quite a bit, alas)

:)
 

sharkeyandgeorge

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Re: Does ' NOW ' exist ?
« Reply #38 on: 07/03/2005 12:49:28 »
I thought super light paritcles like tacheons travelled faster than light how do they beat the rules?
also perhaps now is like a line with only one dimension so although it exists cannot be measured

i apologise for the spelling i know its atrosi atrro attro bad
 

Offline Ultima

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Re: Does ' NOW ' exist ?
« Reply #39 on: 08/03/2005 10:14:44 »
Tachyons are purely theoretical? Although Star Trek might want you to believe otherwise. Because something exists on paper in an equation doesn't mean it occurs in real life. On paper there as a miniscule (to the extreme) chance that if I run at a brick wall I will tunnel right on through un harmed... It's not going to happen, I've tried :D.

http://physics.gmu.edu/~e-physics/bob/n.htm

wOw the world spins?
« Last Edit: 08/03/2005 10:25:48 by Ultima »
 

Offline gsmollin

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Re: Does ' NOW ' exist ?
« Reply #40 on: 08/03/2005 18:49:58 »
I failed in tunneling my fist through a couple of pieces of lumber.
 

Offline chimera

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Re: Does ' NOW ' exist ?
« Reply #41 on: 08/03/2005 20:05:47 »
quote:
Originally posted by gsmollin

I failed in tunneling my fist through a couple of pieces of lumber.



Yeah, those collapsing wavefronts can really hurt the knuckles, eh? :)
 

Offline IAmAI

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Re: Does ' NOW ' exist ?
« Reply #42 on: 08/03/2005 20:37:41 »
I once wondered whether 'now' exists. Consider our perception of ‘now’... In order to perceive anything and take action on (process) anything, we have sense the universe with our senses and store it in our brain. Just like fossils, our brain contains a representation of the past. Therefore, it could be considered that any experience is the past (though minutely so).
 

Offline Sandwalker

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Re: Does ' NOW ' exist ?
« Reply #43 on: 10/03/2005 16:41:45 »
Hey

'Time' comes in 'Any colour you like'

Its all 'Us and them' 'On the run' in 'The great gig in the sky'

So don't 'Speak to me' I'm 'Brain damage'd


Sorry could not get 'Money' or 'Eclipse' to fit in.

:DSo if you can 'Eclipse' this you can have the 'Money'!
 

Offline gsmollin

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Re: Does ' NOW ' exist ?
« Reply #44 on: 11/03/2005 14:07:05 »
quote:
Originally posted by IAmAI

I once wondered whether 'now' exists. Consider our perception of ‘now’... In order to perceive anything and take action on (process) anything, we have sense the universe with our senses and store it in our brain. Just like fossils, our brain contains a representation of the past. Therefore, it could be considered that any experience is the past (though minutely so).



Well, yes, and this is true even if our reaction time were zero, because light has a finite speed. Even across a table, we see each other as we were a few nanoseconds ago. We see the moon as it was 2 seconds ago, etc. This is the whole observer-dependence bit in special relativity. Nevertheless, once the light-cone has past you, it recedes at c, and cannot be recalled, except as a "fossil" memory.
 

Offline Santi2c

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Re: Does ' NOW ' exist ?
« Reply #45 on: 12/03/2005 12:17:57 »
well u can never "sit" on an interval of time, cuz then theres always a way of breaking down that "instant". but of course this all depends. it always goes back to if u believe in "building blocks" or continuos space.  infinite/finite etc.  string theory? we'll always come up with more satisfying conclusions and stuff, but that itching paradox still exists, and whether we choose to accept it or reject it, the paradox will grow.. or shrink? get it? but it all functions the same right, no matter where we are in the scientific timeline? we get similar results no matter how primitive our definition of "things falling to the ground" is.  u may argue that no.. science brings about discoveries and technology and we manipulate the world etc and it benifits us to excercise our curiousity blabla, but after i post this, im still a living human being who might eat somethng or might take a ****, whether it comes outta the microwave or a brick oven, or whether i go in the toilet or behind a tree.  i dont mean to be some arogant little teenage philosopher though, im trying to avoid that.  but like u said "my head's spinning" .. it doesnt nesesarrily benifit the human race to know the answers, but its fun and good excerise, but what does knowing the answer give us.  we invent things like intervals of time to make life more convenient and decorated and controlled and stuff, but then we question our invention/building block.  inventing seconds doesnt give me control of time..
is there a way of understanding time without putting ticks on a clock?  its our need to understand it that brings up this post!  but have u writing an essay for school in one big sitting without thinking, and THEN going back to edit? it seems harder for me sometimes than just rewriting it, or writing it slowly and confidently and thoughtfully the first time around.  but of course, saying that isnt even correct cuz what decides how u move on confidently to the second sentence? either u live life like a caveman without too many questions or u move slowly and find patterns etc, but either way ur still moving through the essay, sorry for the lame double metaphors.  but so much of science is the pedantics, which is me writing this long post hoping for soem attention.  and answers are juicy, especially controversial or unique ones.  coming up with these kinda questions (the frozen time one) is what drive science.  sometimes i wonder if its just another way of "comparing penis size".  like in the end, who really gives a **** about this stuff.  some of the biggest philosophers were some of the biggest tight asses, wanting to be smart, writing down their cyclical complicated thoughts.  theres so much elitism, "who can get the question of the week?" for example. im not sure if i dislike the elitism of science, cuz its kinda fun, and maybe nesesarry.  not sure. so just to clarify, this isnt criticism exactly.  im a jazz trumpet player, and ive noticed that a lot of ppls intentions during a solo vary, but the audience's reaction is always in the back of ur mind, and ppl are boxed into impressing them.  scientists have this similar insecurity.  and again, its all relative, how smart am i in a vacuum? i dunno, let me take a mirror outta my magic hat to reflect ideas off of, or post soemthing here to see how i look.  jazz musicians and scientists have this crazy mix of confidence and insecurity.  this arrogant pride when discovering xyz but this undying need to show it off or gain recognition for it.  so it all goes back to relativity if ur gonna stick posts in the ground in a completely blank white world that u dont understand. so if we need to understand, we must mark up, and stick ticks on a watch. we're dependant on those first urges for knowledge, if we can be satisfied in labeling a "first" of course, whether its miles's playing that got me into jazz (and it was dizzy that got him into it, etc) or plato's questions that sprung up more questions, until it reaches a chemistry textbook that ur obligated to read out of in 10th grade, unless you wanna fail.
this might be too unfamiliar to nonmusicians, although there might be some of u out there, but back to the time question, i find another music connection.  the way u hear music and harmony.  whether you hear the chord that it "presently" sounding, like in a vacuum independently, or whether u hear it as a contrast of the previous chord, and the beauty of the stretch or distacne from A major7 to C#major7. or whether u hear it in relation to "whats to come" or all three? and heres another thought, the zoning in and out thing. whether you zone into the chord, the voicing, the notes A C# E G# in an Amajor7, zoom in further to the vibrations of each note and the sound waves and overtones.... or u zoom out, seeing the chord that just happened and the chord to follow it. u zoom out further and hear all three in your head, you zoom out further and hear how it relates to the 1 song on the album and how it sits infront of the 3 song that is to follow.  or how your perception of that a major 7 chord is effected but the album u heard before putting this one on, or by ur mood, the sound of a glass shattering before u decide to press play, or anythign at all really.  ur attitude when approaching the chord, do u give a **** or do you not give a ****, and ur urge to undrstand the truth. thats what i mean by zoming in and out, and it brings up that question of infinite/finite and reality.  which ever we u crack it, the paradox seems to grow for me.  do you see time as a timeline or a circle or a glowing thing that encompasses ur memories as a child with the presnet with whats to come.  why does everyone see the week days from left to right, why is "the future" to the right, or ahead, or any direction at all.  this sorta relates to kurt vonneguts slaughter house five i guess.  also back to the music thing, some ppl have different theories about how you hear, and no matter if u say u hear oen note at a time and then how it contrasts with the other notes in the chord, or whether u can hear 3 dimensionally, ur still hearing, and ur still deciding that theres a way u hear.  put on chord on top of another on the piano?  isnt it 2d or 3d sounding or what?  asking for answers and asking questions can either bring up more or less, and u have to decide which u want to do i guess.  ok im stopping, and i probably failed at sounding non teenage philosophery, but please respond, with respect,
peace out
 

Offline cheryl j

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Does ' NOW ' exist ?
« Reply #46 on: 29/10/2011 03:01:27 »
I won't even touch the physics involved with time and "now". Its beyond me. But even in biology, there is not exactly an agreed upon "now." Some brain scan experiments show that when a person performs an action, the persons brain has already sent the message to do it before the person is consciously aware of having even made a decision. ( This really creeps me out, as it sort of messes with the idea of free will as well)

Another odd biological thing related to "now" has to do with perception in tall and short people. The nervous system has to correlate sensation in time. If I touch your cheek and foot simultaniously, your brain needs to register both sensations as happening at the same time, even though it takes longer for the nerve impulse to get from your foot to your brain than from your cheek to your brain. There is a slight delay in the nerve transmission from the cheek, so they arrive at the same time. This delay is less in shorter people than in tall ones, and in this respect shorter athletes have an advantage over taller ones, since they perceive events as happening slightly sooner than tall people. Since nerve transmissions travel pretty fast, you wouldnt think the difference would be that significant, but it as much as a tenth of a second, which if you are judging the speed and position of a fast ball, might matter.
« Last Edit: 01/11/2011 16:14:15 by cheryl j »
 

Offline neilep

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Does ' NOW ' exist ?
« Reply #47 on: 29/10/2011 12:26:04 »
I won't even touch the physics involved with time and "now". Its beyond me. But even in biology, there is not exactly an agreed upon "now." Some brain scan experiments show that when a person performs of action, the persons brain has already sent the message to do it before the person is consciously aware of having even made a decision. ( This really creeps me out, as it sort of messes with the idea of free will as well)

Another odd biological thing related to "now" has to do with perception in tall and short people. The nervous system has to correlate sensation in time. If I touch your cheek and foot simultaniously, your brain needs to register both sensations as happening at the same time, even though it takes longer for the nerve impulse to get from your foot to your brain than from your cheek to your brain. There is a slight delay in the nerve transmission from the cheek, so they arrive at the same time. This delay is less in shorter people than in tall ones, and in this respect shorter athletes have an advantage over taller ones, since they perceive events as happening slightly sooner than tall people. Since nerve transmissions travel pretty fast, you wouldnt think the difference would be that significant, but it as much as a tenth of a second, which if you are judging the speed and position of a fast ball, might matter.

Woo !!..Thank ewe Cheryl (and welcome to the site  :D) for this wonderful informative post. That is fascinating regarding the cheek and foot !..So..the brain purposely delays the reaction from the cheek to correspond in time with the reaction from the foot !......

So, if just the cheek is touched the reaction is quicker !...amazing !
 

Offline cheryl j

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Does ' NOW ' exist ?
« Reply #48 on: 01/11/2011 16:13:25 »
If I understood the article I read correctly, I dont think the nerve transmission is faster if just the cheek is touched. I think no transmission is allowed to go any faster than if it had originated from the farthest point from the brain, so in tall people it will always be a little slower.
 

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Does ' NOW ' exist ?
« Reply #48 on: 01/11/2011 16:13:25 »

 

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