Does Time Actually Exist?

[marcel_leonard]

An Extremely Breif History of Time:<br /><br />In 1687 Sir Issac Newton claimed that the universe has one absolute clock.<br /><br />In 1905 Albert Einsten claimed that every observer has his/her own [accurate] clock.<br /><br />In 2002 I like many others wondered if time actually exists, or is simply just an illusion created by our need to compensate for our relatively short life spans? <div class="Discussion_UserSignature"> "A mind is a terrible thing to waste..." </div>

 

[jurgens]

our life span is short in what sense?

 

[kmarinas86]

Time is not an object. Time is percieved just how colors, touch, taste, etc, can percieved and measured too. Rate of change (time) increases with the strength of the gravity field and the relative velocity.<br /><br />http://en.wikipedia.org/wiki/Time_dilation<br /><br />Time cannot be contained inside an hourglass. The space-time continuum is not a object (neither is time or space independently), and thus is does not exist as an object does.<br /><br />Therefore it must be an abstract concept and a non-object we must adapt to. If everything was the same all the time, there would be no time, and no conciousness.

 

[grooble]

Yes, the older you get, the faster time goes.<br /><br />Your life is half over when you reach 17, perspectively.

 

[kmarinas86]

My life ain't half over already! <img src="/images/icons/tongue.gif" />

 

[daniko]

Hi there !<br /><br />I'll try to make a more simple picture of what Time is.<br /><br />As my impressions on General Relativity are, the Time is defined by the rate things happen ?!?<br />For example: the rate of fission of caesium in a caesium clock or the rate of photon emittion from an atom.<br />As a whole - the rate everything observable happens.<br /><br />So the GR tels us that things in other places as we observe them may happen in "slower rate" according to "our observations" due to gravity or relative speed.<br /><br />And the Time is reciprocal of the rate the things happen !<br /><br />I hope it makes some sence <img src="/images/icons/smile.gif" />

 

[kmarinas86]

In general, the period of motion of smaller particles is shorter than the period of motion for large objects. Electrons are blazingly relativistic and travel billions of billions of billions, etc. times their diameter in a second. Atoms travel around the earth slower than electrons do around the nucleus of atoms, and the radius is even larger, meaning that they take a longer time to under go a "period" - i.e. to even travel merely billions of times their diameter. The same with goes with planets in general, whose period is longer than atoms. Likewise, the period for stars in spiral galaxies is much larger than the period of planets. The period is proportional to level of emergence, or the hierarchy of the universe. Time is inversely proportional to the period and this hierarchy.

 

[a_lost_packet_]

<font color="yellow">marcel_leonard - ..In 2002 I like many others wondered if time actually exists, or is simply just an illusion created by our need to compensate for our relatively short life spans? </font><br /><br />I think, what you are asking is "Is the concept of time a human construction?"<br /><br />Well, the measurements we place upon time may be human-constructed. Also, for quantum objects, time may have a very different meaning. However, in the macro world in which we live, time is very real. The simplest example would be "entropy." Where a state of change takes place over time in which there is an increase in the amount of energy, over time, that is not available to do "work." Most commonly, this is used to refer to ordered and disordered states. We can not reverse entropy without adding energy to the system, changing the process.<br /><br />Thermal equilibrium would be another example that is demonstrated over time by using a simple glass of water and ice. As heat energy is transferred over time to the glass and water/ice mixture, the ice melts. Depending on outside conditions, over time, the water in the glass will eventually reach a thermal equilibrium with the outside temperature. This is irreversible. We can not "add cold" to the water. We can only retrieve it and remove heat, thus influencing the process by adding energy.<br /><br />Neither of these examples are dependent upon human interaction in order to proceed through their natural, time-dependent (in the examples) respective processes. Both will occur with or without our observation. Of course, we won't know about that unless we observe the results. <img src="/images/icons/wink.gif" /><br /><br />Time is real. However, depending on what we are looking at, we may see things that behave differently in regards to the linear "time" we experience in the macro-world.<br /><br /> <div class="Discussion_UserSignature"> <font size="1">I put on my robe and wizard hat...</font> </div>

 

[5stone10]

Its, like, real man !!

 

[5stone10]

<font color="yellow">In 2002 I like many others wondered if time actually exists...</font><br /><br /><br />What's so special about 2002?

 

[daniko]

I've got an idea about why we had never observed things that happen in reverse ( where Time goes backward )<br /><br />I think that the matter is about the direction the information goes:<br /><br />1. If we observe something that happens near us, the information flows from the events toward as with normal speed.<br />2. If we observe something that happens on a high speed spaceship (1/2 lightspeed), the information flows from the events toward us in reduced speed as things happen in slow motion<br />3. If we observe something that happens in strong gravity (near black holes <img src="/images/icons/rolleyes.gif" />), the information flows from the events toward us also in reduced speed as things happen in slow motion<br />4. If we try to extrapolate in this direction of thoughts then - /><br />If we observe something that happens in a place where time goes backward compared to ours, the information flows from the events toward us in negative speed.<br />-- /> So we'll never receive information of that things happening in reverse <img src="/images/icons/shocked.gif" /><br /><br />How about that <img src="/images/icons/smile.gif" />

 

[daniko]

I'm sorry but I'll disagree about the speed of information flow !<br /><br />First: Waht is this thing speed of information ?<br />-- /> Simply this is bitrate. How many bits of information you get for a second of your local time<br /><br />Second: What is a bit of information in the physical world ?<br />-- /> Simply this is a photon (light quantum)<br /><br />Let us suppose that the "Hhhheeeeelllloooo Ddddaaaannnniiiikkkkoooo" message consists of 41 photons emmited consecutively<br /><br />If the whole message is send by an astronaut near a blackhole for 1 sec his time (from the first to the last photon), we will be recieving it for 10 sec (this slow for example)<br />So the astronauts local "bitrate" is 41 photons/sec while ours is 4,1 photons/sec<br /><br />Now suppose we shut down the blackhole <img src="/images/icons/wink.gif" /> and the astronaut emits exactly the same message again<br />-- /> the bitrate in which we recieve his information will jump from 4,1 photons/sec to 41 photons/sec<br /><br />Thats what I ment <img src="/images/icons/smile.gif" /><br />

 

[kmarinas86]

A photon escaping from a blackhole is redshifted. Once it escapes that gravitational field, it's traveling through an area with less time dilation. At all times, the photon is travelling at the speed of light as it is within the medium it travels. c/v = the refractive index of the medium, which is greater than 1 when there is gas and dust around, like in Earth's atmosphere.<br /><br />http://en.wikipedia.org/wiki/List_of_indices_of_refraction

 

[vogon13]

<br /><br />Without time, would everything happen all at once, or would nothing happen at all ?<br /><br />David Letterman<br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[yevaud]

"Time is nature's way of making certain that everything doesn't happen all at once..." <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[siarad]

<blockquote><font class="small">In reply to:</font><hr /><p>Second: What is a bit of information in the physical world ? <br />-- /> Simply this is a photon (light quantum) <p><hr /></p></p></blockquote><br />Not sure I can agree with that as bits per second can be higher than state changes per second, your photon. It is in our electronic communication where there are many bits per state change.<br />This doesn't detract from your post but carrier & information therein are not directly equal due to encoding.<br />This doesn't mean information exceeds C due to more bits per second than carrier but bps shouldn't be equated to speed.

 

[serak_the_preparer]

It may all be in the mind. As theoretical physicist and philosopher Julian Barbour puts it:<br /><br />'<i>My basic idea is that time as such does not exist.</i>'<br /><br />- from The End Of Time: A Talk With Julian Barbour by John Brockman (Edge), August 16, 1999<br /><br />I highly recommend the article.

 

[daniko]

High !<br /><br />I was away for a while but now I'll try to answer all your remarks.<br /><br />First to <font color="blue">siarad</font>s note:<br />Yes, I agree that my post about "the speed of information flow" was not very precise. That's because I just wanted to make an example of what I mean by "information flow" in the context of physics and what "speed of information" would be like. In fact the information could be carried by everything that can travel through the 4D spacetime.<br /><br />Second to <font color="blue">ranur</font>s note:<br />Yes, I think there are areas in the 4D spacetime where time flows in reverse direction respective to ours.<br /><br />For to be a little more specific I'll add some lines:<br /><br />1. When physicists want to express that things happen in determinated succession (one after another) they use the "<b>arrow of time</b>". I preffer to look at "<b>arrow of time</b>" as the <b>single vector of the Time</b> in 4D spacetime.<br /><br />My assumption is that:<br />When we observe something in different spacetime context, we "see" the orthogonal projection of it's <b>single vector of the Time</b>. The more twisted is the observed spacetime, the smaler orthogonal projection we observe. But when the twist angle reaches 90 degrees (virtually when the two <b>single vectors of the Time</b> become orthogonal) we cannot see anythig happening in the observed spacetime. For example when something travels in the speed of ligh compared to us.<br /><br />2. The way we take information from the outer world is by using our sensors. Our sensor for Time is our memory. The way we feel the time is by the order of things we learned stored in our memory<br /><br />My assumption is that:<br />Our sensor for Time is not capable of sensing any information coming form spacetime zone so twisted that the orthogonal projection of its <b>single vector of the Time</b> has oposite direction to ours.<br /><br />There might be a stronger assumption that:<br />In

 

[emperor_of_localgroup]

Serak, thanks for the link to Julian Barbour. The name sounds familiar. I think I understand what he's saying. His 3 main points are:<br />1) There is only NOW. There is no past, no future. our memory is nothing but a recording media for an event.<br />2) There is a relation between time and motion - which hints to a discrete nature of time.<br />3) The universe is static, because only thing we have is NOW. This scares me.<br /><br />I dont think, even if he's right, any of the scientific theory will be affected by this idea of time. <div class="Discussion_UserSignature"> <font size="2" color="#ff0000"><strong>Earth is Boring</strong></font> </div>

 

[daniko]

Thank you both (<font color="blue">Serak</font>and <font color="blue">Emperor</font> for making me look at Julian Barbour's interview.<br /><br />It's quite interesting poin of view. I couldn't understand the core logic of Barbour's theory but here's what I think I found:<br />He is trying to decide the conflict between General relativity and Quantum mechanics.<br />The conflict:<br />QM -- /> a single particle (like the electron) could be in more than 1 dispositions simultaneously.<br />GR -- /> nothing could be in several places simultaneously because the ban of the lightspeed limit.<br />The decision of Barbour:<br />No Time -- /> No problem<br /><br />So he spent 30 years experimenting with this thought (that's persistence).<br /><br />If Barbour's theory brings the conclusion that there's nothing new to happen - I don't like it ! <img src="/images/icons/smile.gif" /><br />But there was something that was close to my previous post. He presumes that humans memory is the sensor for detection of Time. He also presumes that this sensor is not perfect. So the question is:<br /><br />What aspect of Time our memory sensor misses ?<br /> <br />May be our memory works as Time-diode and we memorize only things that happen our Time-way<br />But may be the Univers itself has such Time-diodes that prevents the <b>cause and effect</b> dependencies

 

[igorsboss]

Here are some pieces of my own personal philosophy.<br /><br />Abandon ye all hope of a better past. (This is forgiveness.)<br /><br />Abandon ye all hope of a perfect future. (Perfection is an illusion.)<br /><br />Choose now. Choose well.

 

[i_think]

My memory can't sense time. Sometimes last week seems like last month, and last year feels like yesterday. I remember events, and if I'm lucky I remember their correct sequence. Events do not represent time; they merely serve as markers for the passage of time. I only remember 1969 only because I remember myself as a young boy staring at the moon in amazement to think that men were actually walking on it. That's an old memory that seems like a recent one in my mind.<br /><br />Events mark the passage of time, and time determines the pace at which these events may occur. What are events but cause and effect. So time controls the pace of cause and effect, and it seems that in the quantum world we can on occasion observe the effect prior to the cause. This is the part that is elusive to understand and suggests that we may have a false notion of time - and space because cause and effect also require space in which to happen. So it makes sense that space is related to time. That's it for now, I'll go and enjoy the present as suggested!

 

[daniko]

Hi guys !<br /><br />I see your point (<font color="blue">igorsboss</font>and <font color="blue">I_think</font>. That's may be the way <b>96%</b> of the people prefer to think of Time. It's the Local Person Time:<br />The past is so close that you can almost touch it<br />The future is so familiar that it could almost be mistaken for the past<br /><br />That's how a nice quiet old man feels it <img src="/images/icons/smile.gif" /> (Like Julian Barbour)<br /><br />But I'm from the other <b>4%</b>.<br />For me the future must be enough far, that it's not predictable nor precalculatable. That's what thrills me !<br /><br />About the memory and how it senses the time:<br />Our memory is multifunctional and it serves many purposes, so the sence of Time is a small part. The trace that Time leaves in our memory is not the facts we remember but the links of timely order between the facts.<br />Of course <font color="blue">I_think</font>is right that when things are in bigger distance our memory can play tricks. That's because of the mechanism that flushes unused information, but that don't change the fact that in relatively short past we really sense the Time.<br />

 

[serak_the_preparer]

Emperor,<br /><br />You're welcome. I find Barbour's thoughts on the nature of time to be the most intriguing of anyone out there writing on the subject. I agree with all your points. I will need to read Barbour again, and closely, to be more sure of my own understanding.<br /><br />But my understanding of Barbour as it stands right now is that some configurations of the universe are so highly probable, and so similar to one another, that they overlap enough for an overall consistency between them to exist. Some Nows are very much like other Nows, sustaining the illusion of a flow from one to the other, which illusion Barbour recognizes as time. Every possible configuration exists, at least potentially, but the potential for some is much higher than the potential for others, based on the equation which describes the universe. Barbour suggests this equation is some version of the Wheeler-DeWitt equation.<br /><br />This description of time is of very little practical value to us as we humans live our lives and experience something we call time. But, if ever proven, it would have a considerable impact on cosmology. Barbour proposes that, when time 'breaks down' as physicists attempt to come to grips with what's happening near or at the Big Bang, it is because time doesn't belong in the picture in the first place.<br /><br />The Wheeler-DeWitt equation, which describes the universe without resorting to time, predicts a very low value for the cosmological constant. As we refine our measurements of the Cosmic Microwave Background Radiation and fine-tune our measurement of the rate of the universe's expansion, we will close in on the actual value of the cosmological constant. Which in turn will inform us just how close Wheeler and DeWitt have struck, and whether time is actually part of the description of the universe.

 

[poodown]

Yes. *avoids long reasoning why*