Friday, February 18, 2011

What is time?

Is time a dimension? A process? An illusion? A currency? Does it slow down under the influence of motion or gravity? Do clocks really measure it?

What is time? We know that time is relative. This is not to say that each person has a mentally different experience of time, which is also true, but that at the physical location of person A, regardless of his/her emotional or perceptional experience of time, the speed of time is different from person B if person B is moving relative to person A.  This leads us to the twin paradox:
In physics, the twin paradox is a thought experiment in special relativity, in which a twin makes a journey into space in a high-speed rocket and returns home to find he has aged less than his identical twin who stayed on Earth. This result appears puzzling because each twin sees the other twin as traveling, and so, according to a naive application of time dilation, each should paradoxically find the other to have aged more slowly. In fact, the result is not a paradox in the true sense, since it can be resolved within the standard framework of special relativity. The effect has been verified experimentally using measurements of precise clocks flown in airplanes and satellites.

... Both gravitational time dilation and special relativity can be used to explain the Hafele-Keating experiment on time dilation using precise measurements of clocks flown in airplanes. - wiki

To understand time, begin by understanding special relativity:
In special relativity there is no concept of absolute present. A present is defined as a set of events that are simultaneous from the point of view of a given observer.

File:Time dilation02.gif

The green dots and red dots in the animation represent spaceships. The ships of the green fleet have no velocity relative to each other, so for the clocks onboard the individual ships the same amount of time elapses relative to each other, and they can set up a procedure to maintain a synchronized standard fleet time. The ships of the "red fleet" are moving with a velocity of 0.866 of the speed of light with respect to the green fleet.

The blue dots represent pulses of light. One cycle of light-pulses between two green ships takes two seconds of "green time", one second for each leg.

As seen from the perspective of the reds, the transit time of the light pulses they exchange among each other is one second of "red time" for each leg. As seen from the perspective of the greens, the red ships' cycle of exchanging light pulses travels a diagonal path that is two light-seconds long. (As seen from the green perspective the reds travel 1.73 (\sqrt{3}) light-seconds of distance for every two seconds of green time.)

One of the red ships emits a light pulse towards the greens every second of red time. These pulses are received by ships of the green fleet with two-second intervals as measured in green time. Not shown in the animation is that all aspects of physics are proportionally involved. The light pulses that are emitted by the reds at a particular frequency as measured in red time are received at a lower frequency as measured by the detectors of the green fleet that measure against green time, and vice versa.

The animation cycles between the green perspective and the red perspective, to emphasize the symmetry. As there is no such thing as absolute motion in relativity (as is also the case for Newtonian mechanics), both the green and the red fleet are entitled to consider themselves motionless in their own frame of reference.

Again, it is vital to understand that the results of these interactions and calculations reflect the real state of the ships as it emerges from their situation of relative motion. It is not a mere quirk of the method of measurement or communication. - wiki

Here is time as a currency from timephysics.com


http://www.timephysics.com/sitebuilder/images/TIME_AS_CURRENCY2-960x530.jpg
Time becomes evident through motion and is measured by comparison with other motions. Sunrise sunsets, night and day, the changing seasons, the movement of the celestial bodies are all indicative of continuous change.  The aging process is a reminder that molecular  motion and interactions are also at work and are a part of time. Other very important aspect of time is presence of motion of particles like photon and motion at atomic level.

From point of view of physics ... Time is the presence of motion and forces and is caused by the expansion of space.

15 comments:

Mirlen101 said...

Time = relative difference . Time is everything ! Not something we made up or just use as a tool ! Time is imbalance , it is existence itself. Time/space = matter . Matter is just differences in Time/space. Matter is time/space ripples , distortions .All of what we know and perceive is by these time/space indifferences . Time/space does not exist without indifference ( in balances ) it is indifference itself , without these imbalances we have no gravity no matter , energy.Everything ceases to exist ! It balances to a singularity .No time, no space, no matter or energy , NOTHING ! Think of time/space as a sheet of water with no reflections . The water is invisible because of no reflections . The only way to see the water or its effect is when a drop disturbs the surface ( imbalance )The water would cease to exist until there was a disturbance . That's sort of how time/Space etc works . The fabric of time/space is not there until it is disturbed , put out of balance .

arjay001 said...

All are in the present moment.

Mirlen101 said...

There is no present moment .That is the point . The only "Present moment " is the moment of creation the " singularity " when all is the same and nothing at the same time and point . Even then "moment" doesn't really exist . So there is really no such thing as present moment. Everything is in it's own time/space ( time zone )

ileana said...

What is time? It would be nice to know... :)

In Alaje's talks Part 4 ( http://www.youtube.com/watch?v=y9R_GIP9eFo&feature=related ) he says "everything is energy and time does not exist in the higher realms. Time is only a 3D - earth-concept. Time and space [are] flexible."
<3

Mirlen101 said...

I just told you what time is weren't you listening ? ;-) It's really not that complicated ! Just hard to get ones mind around it . Think of time/space as a spring . At one end you have one reference point at the other end is another ( relative ) reference point. As the two ends get farther apart the spring ( space/Time ) stretches and constricts. If the two points are moving inward towards each other the spring compresses and expands outward . You can use the same analogy with a wave form . Alaje’s talks are spiritual and philosophical not scientific. But some of what he says does apply .But time is not an earth concept ! I believe Alaje was speaking in metaphysical philosophical terms .The wave forms he speaks of is a good example .The measurement of the length and width of those frequency waves he speaks of is TIME/SPACE ! E=Mc squared ! It's all about space ( distance between ) and time ( difference ) one in the same virtually they can't be separated !If anything is earth based it is metaphysics ! Not to say metaphysics is all hocus pokus there is a lot of insight there . You just can't take it too scientifically . It isn't as concrete as math ( scientific analysis ).

Sepp said...

What is time? That is a loaded question.

No one here (not here on this blog, but here on this planet) really knows.

Actually, time is at the basis of physical existence. Without time, no universe, at least not the one WE know, where time is a linear flow from past, through the moment of the present, to a still uncertain future.

For matter to exist at all, it has to persist. And persistence implies time - the change from one moment, one state, to another.

It's complicated.

Mirlen101 said...

Well said , but it is complicated and simple at the same time ! ;-) Just hard to fathom . People can't think very well in 3 or more dimensions at the same time . And we are not used to thinking of our existence as fluid ;-)

Sepp said...

Indeed it's hard to fathom.

We are not used to look at the basis of existence. Too far down the rabbit hole.

We invent things like the big bang and relativity so we don't have to look further. It's all clear, says science ... but is it really, or are we just putting our head in the sand?

Mirlen101 said...

I can just about guarantee that Quantum physicists are off . I think Einstein was more on track . They are always trying to prove him wrong .Quantum physics is too close to philosophical opinion or mumbo jumbo. I would call most of it ego science . Similar to when people thought the universe revolved around them .I think one thing is clear no time no nothing ;-)Or no time > know nothing ;-)
As for a master plan or planner I'm sure it is beyond me or anyone else so why go there ;-)

Xeno said...

How does your view explain that quantum science has been shown repeatedly in experiments over years to be correct?

Mirlen101 said...

I'm not saying quantum physics is wrong as a whole . Einstein virtually invented quantum physics !I'm mostly referring to things like string theory , multiple parallel universes ( as in I'm everywhere , I'm everywhere ! ;-/ Schrödinger's cat ! <ego science ! The original idea that Einstein didn't object to was that you can't observe the smallest of particles because the instruments you use to view them would change the outcome ( state of being ) not as later believed by quantum physicists that the outcome doesn't exist until YOU the viewer witnesses it ! <ego science ! That's the kind of thing Einstein objected to . The uncertainty principles . He believed that the uncertainty was in the viewer not the view or should I say View-E ;-) He believed the uncertainty would be eventually cleared up by more scientific scrutiny . Mostly by the unification theory being realized . Think of all of what is not known for certainty like gravity ! Most of what is known today is directly from Einstein ! Or Newton ! Not from theoretical quantum physicists ,< that is an unknown quantity ;-) Most of what has been found by research has been found by observation . Not by theoretical Quantum physicists based on the uncertainty principle ! Name one thing that works by that process . I mean a working product or process of the uncertainty principle ! And not an experiment that is an "interpretation" It's like proving a negative !

arjay001 said...

"The Present Moment" I am in need of the word for the moment I live in. I do not live 5 minutes in the future or 5 minutes in the past. So where am I right at this moment, however brief it is? Do you say, "in real time"? How about a cool name something like, "Hyperplane in Space-Time"?

Thanks for your help!

Xeno said...

A songwriter friend of mine had a song that worked for this: "we are surfers of the now."

Mirlen101 said...

@arjay001 “Hyperplane in Space-Time” that's good , I like that one ! ;-)

uniontera said...

This Youtube is more interesting than turning geocentric theory into heliocentricism, and don't lag behind although it is
compared with Jesus walking on water.
I will show you Jesus christ with physics. He is at step 2 on this youtube.
JESUS CHRIST PHYSICS (making mass) http://youtu.be/AN1jTwHUC7E?a
Just trust me. You can touch a time. - contemporary artist Jae heung, Ahn