Is Time Travel Possible Through Mental Projection?

AI Thread Summary
Time is conceptualized as a measurement of motion through three spatial dimensions, with the future being more accessible than the past due to the need for reversing all particle motion to travel back in time. Mental time travel is proposed as a possibility, especially during sleep, where dreams may allow for a conscious experience of different temporal states. The discussion emphasizes that time is often viewed as the fourth dimension, integral to understanding spacetime, which combines three spatial dimensions with time. The nature of time, its dimensionality, and its relationship with motion are debated, with some asserting that time exists independently of motion. Ultimately, the conversation explores the complexities of time travel, both physically and mentally, within the framework of current scientific understanding.
Noah
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Time is just a way of measuring the velocity of the motion of an object through the 3 real dimensions. In order to go into the future you would have to stop your particles for the desired amount of time (basically cryogenics). Your particles weren't present to have their effect on the future so the outcome would be slightly different than what it would have been. In order to go into the past you would have to reverse the past motion of all other particles in the universe (an exact reverse of physical law that affects everything but you). Going by that logic, I am lead to 'believe' that going into the past is literally impossible, but going into the future isn't very difficult at all. Now, if you are one that believes (I'm not saying I are or aren't) that the mind is immaterial then that still leaves the possibility for mental time travel. Any thoughts would be appreciated.
 
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Time is the 4th dimension. Why? We've defined it that way.
 
In all dreamscapes, the past and future are equally likely pictures. It seems that only during the minimum mental activities of sleep can one moves into the past or into the future. The dangers are recurrent nightmares that go around in circle, repeatedly.
 
russ_watters said:
Time is the 4th dimension. Why? We've defined it that way.

Length, width, and depth are real dimensions whether we define them or not. Time is a measurement associated with velocity and position. Time and velocity would still exist in 1 and 2 dimensional space.
 
Antonio Lao said:
In all dreamscapes, the past and future are equally likely pictures. It seems that only during the minimum mental activities of sleep can one moves into the past or into the future. The dangers are recurrent nightmares that go around in circle, repeatedly.

Remembering the past isn't what I really meant by mentally time traveling. I meant a conscious experience of time traveling. It's my personal belief through observation that dreams don't have any significance to consciousness. They are just a side effect of theta wave sleep. Interestingly enough, during theta wave sleep the brain matches the Schumann resonance.
 
Noah said:
Length, width, and depth are real dimensions whether we define them or not.
What if I choose polar coordinates?
 
Noah said:
Length, width, and depth are real dimensions whether we define them or not. Time is a measurement associated with velocity and position. Time and velocity would still exist in 1 and 2 dimensional space.

How can velocity exist in one dimensional space? Ther would seem to be nowhere to go!
 
mee said:
How can velocity exist in one dimensional space? Ther would seem to be nowhere to go!

Velocity in 1 dimension space would be constant at the speed of light.

The photon has no mass, so it can be considered to be dimensionless.
A photon traveling in a straight line would be moving in a single dimension - forwards.
Any object larger than a photon would have mass so would require 3 dimensions.

Our perception of visual objects is through a multitude of photons all moving in their own single dimensional trajectory.

Time for a photon would the 2nd dimension.
 
AWolf said:
Velocity in 1 dimension space would be constant at the speed of light.

The photon has no mass, so it can be considered to be dimensionless.
A photon traveling in a straight line would be moving in a single dimension - forwards.
Any object larger than a photon would have mass so would require 3 dimensions.

Our perception of visual objects is through a multitude of photons all moving in their own single dimensional trajectory.

Time for a photon would the 2nd dimension.
Do you really believe that something (an object, a particle, etc) is not fully evolving in 3D? Thus only active in a flatland? Or even dimensionless? Hum.
 
  • #10
If a photon had mass, and dimensions, then relativity would make it extremely hazadous to stand in front of a flashlight - you wouldn't notice tghe photon's at rest mass, but its relativistic mass would leave a mark.

Before the Big Bang (assuming it happened) there was a singularity. All the energy of the universe contained in a dimensionless point.

All matter has dimensions, energy does not.
 
  • #11
russ_watters said:
What if I choose polar coordinates?

Polar coordinates are a measurement of two dimensions (length/width - latitude/longitude). The surface of the Earth only has two dimensions. If we could easily travel through the inside of the Earth we would need to add a third dimension to our polar coordinates.
 
  • #12
AWolf said:
If a photon had mass, and dimensions, then relativity would make it extremely hazadous to stand in front of a flashlight - you wouldn't notice tghe photon's at rest mass, but its relativistic mass would leave a mark.

Before the Big Bang (assuming it happened) there was a singularity. All the energy of the universe contained in a dimensionless point.

All matter has dimensions, energy does not.

Voltage, amplitude, and wavelength. There's your three dimensions for energy.
 
  • #13
Noah said:
Polar coordinates are a measurement of two dimensions (length/width - latitude/longitude). The surface of the Earth only has two dimensions. If we could easily travel through the inside of the Earth we would need to add a third dimension to our polar coordinates.
Yes, you can have 3d polar coordinates. My point though, was that polar coordinates are not length, width, and depth. But they still work.
 
  • #14
russ_watters said:
Yes, you can have 3d polar coordinates. My point though, was that polar coordinates are not length, width, and depth. But they still work.

But only because the third dimension is already known, right? If you give someone your location in lattitude and longitude, they still don't know where you are unless they know that altitude is assumed to be "ground level". This gives them their third coordinate.

Noah,
I pretty much agree with your original post. Most of the time I find it usefull to think of time as simply another word for space. Knowing that speed and direction are the same property seen from two different perspectives, and that speed is a time-like measurement, while direction is a space-like measurement, I can logically deduce that space and time are likewise the same property seen from two different perspectives (even if I can't allways grasp it intuitively).
 
  • #15
russ_watters said:
Yes, you can have 3d polar coordinates. My point though, was that polar coordinates are not length, width, and depth. But they still work.

The polar coordinates are length and width. Look at a flat map of the world. The depth is still there but not measured because we live on the surface of the Earth. If we ever start living at the bottom of the sea, then we will add a depth to the polar coordinates.
 
  • #16
LURCH said:
Noah,
I pretty much agree with your original post. Most of the time I find it usefull to think of time as simply another word for space. Knowing that speed and direction are the same property seen from two different perspectives, and that speed is a time-like measurement, while direction is a space-like measurement, I can logically deduce that space and time are likewise the same property seen from two different perspectives (even if I can't allways grasp it intuitively).

Time is motion through space. Without motion, time does not exist.
 
  • #17
I think, force is spacetime (combined 3-space and 1-time). This is what Einstein had already shown in his general theory of relativity. He said that the gravity force is the same as the curvature of spacetime.
 
  • #18
Antonio Lao said:
I think, force is spacetime (combined 3-space and 1-time). This is what Einstein had already shown in his general theory of relativity. He said that the gravity force is the same as the curvature of spacetime.

Einstein used the curvature of SpaceTime to explain the force of gravity - Gravity Well.
 
  • #19
Wow. OK, let's go over this. If I want to specify an event, I need 4 numbers: latitude, longitude, altitude, and time. Hence four dimensions. Or look at it this way: An object could hardly exist with width and length but no depth; there would literally be no distance between one side and the other! Nor could something exist with length, width, depth, but no duration. It would pop out of existence the same instant it popped into existence! Hence, four dimensions.
 
  • #20
Of course time is the fourth dimension...by your logic, it exists no matter whether we define it or not.
 
  • #21
ZelmersZoetrop said:
Wow. OK, let's go over this. If I want to specify an event, I need 4 numbers: latitude, longitude, altitude, and time. Hence four dimensions. Or look at it this way: An object could hardly exist with width and length but no depth; there would literally be no distance between one side and the other! Nor could something exist with length, width, depth, but no duration. It would pop out of existence the same instant it popped into existence! Hence, four dimensions.

A point moving through any of the three dimensions experiences time because it is moving. Time does not exist without motion. If anything, time is a +1 dimension to any existing dimension. In other words, time is a property of a dimension to measure motion in that dimension (it takes time to get from point A to point B on a 1 dimensional line, but if the point doesn't move time doesn't exist for it).

An object doesn't (not just hardly) exist with width, length, and no depth. 1 and 2 dimensional objects are just abstract concepts.
 
  • #22
Time is really the 3n+1 dimension. The 3n is cyclic of 3 space dimensions where n is a positive integer. But when n is a rational number, including fractions, then the 3n dimension of space becomes fractal (fractional dimension).
 
  • #23
Alright. I'll go over this in a slightly different way. The Minkowski metric tensor can be displayed as a 4X4 matrix. Hence, four dimensions. Doubting the existence of time as a dimension is doubting SR.
 
  • #24
Let's say I define a set to be made up of four members John, Paul, George and Eric. Doubting that time is a dimension of spacetime is like doubting that Eric is a memebr of this set: completely nonsensical, as Eric is a member of this set by defintion just like time is a dimension in spacetime by definiton. You can dispute the effectiveness of theories which use spacetime continuums if you like, but there's simply no room to argue whether or not time is the fourth dimension of spacetime, as it is by definition.
 
  • #25
The other question to ask is why the dimension of time remains 1 dimensional while the space dimension changes.

SR and GR - space is 3 dim and time is 1 dim.
Superstring - space is 9 dim and time is 1 dim.
M-Theory - space is 10 dim and time is 1 dim.

Time is the 1-dim that makes spacetime 4-dim.
Time is the 1-dim that makes superstring 10-dim.
Time is the 1-dim that makes M-Theory 11-dim.

Time is really one dimensional. Its dimensionality will never change in any physical theory.
 
  • #26
By "could hardly exist," Noah, I meant not "could barely exist" but rather "could not conceivably exist." I should have made that clear in my post.

Time most certainly exists without motion. It is represented by a vertical world-line in a space-time diagram.
 
  • #27
I agree that time is not the 4th dimension. I can see the 4th dimension using tetracubes and such but i need to find and equation to explain it. the closest thing i have is (2x + 1)^4 (4th dimension) = 16x^4 + 32x^3 + 24x^2 + 8x +
1. can anyone confirm this equation
 
  • #28
Going into the future is indeed not very difficult at all. In fact, I am doing it right now... watch: One Mississippi, two Mississippi, three Mississippi.
 
  • #29
bazucajoe10 said:
I agree that time is not the 4th dimension. I can see the 4th dimension using tetracubes and such but i need to find and equation to explain it. the closest thing i have is (2x + 1)^4 (4th dimension) = 16x^4 + 32x^3 + 24x^2 + 8x +
1. can anyone confirm this equation

As I said time most defintiely is a dimension of spacetime simply by definition. That said saying that time is/is not the fourth dimension is virtually meaningless; you have to define what time is the fourth dimension of.

I'm not sure what your're trying to communicate with you're equation, bu there's a simple equation that explains a 4-dimensional Euclidian space:

ds^2 = {dx_1}^2 + {dx_2}^2 + {dx_3}^2 + {dx_4}^2

The fourdimensional equivalent of a cube is called a tessseract.
 
  • #30
Noah said:
Length, width, and depth are real dimensions whether we define them or not. Time is a measurement associated with velocity and position. Time and velocity would still exist in 1 and 2 dimensional space.
(n+1)-dim is the TIME for n-dim.
Michael.
 
  • #31
AWolf said:
The photon has no mass, so it can be considered to be dimensionless.
Specify, please, what photon you mean. . Some of them have definitely mass.
 
  • #32
Antonio Lao said:
The other question to ask is why the dimension of time remains 1 dimensional while the space dimension changes.

SR and GR - space is 3 dim and time is 1 dim.
Superstring - space is 9 dim and time is 1 dim.
M-Theory - space is 10 dim and time is 1 dim.

Time is the 1-dim that makes spacetime 4-dim.
Time is the 1-dim that makes superstring 10-dim.
Time is the 1-dim that makes M-Theory 11-dim.

Time is really one dimensional. Its dimensionality will never change in any physical theory.

This has been a https://www.physicsforums.com/showthread.php?t=24988 for me in regards to time.

Without time in any of these scenario's, then all we have is frames of reference? If we do not include time, the dynamical nature of any of these "actions" could not be realized?

Would this be a be a fair assumption?
 
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  • #33
Michael F. Dmitriyev said:
Specify, please, what photon you mean. . Some of them have definitely mass.

The overwhelming consensus among physicists today is to say that photons are massless. However, it is possible to assign a relativistic mass to a photon which depends upon its wavelength.
 
  • #34
AWolf said:
The overwhelming consensus among physicists today is to say that photons are massless. However, it is possible to assign a relativistic mass to a photon which depends upon its wavelength.
X-ray and Gamma both being "photon" aren’t massless.
 
  • #35
Michael F. Dmitriyev said:
X-ray and Gamma both being "photon" aren’t massless.
Note please, this part of AWolf's post:
The overwhelming consensus among physicists today is...
Whether your idea is right or wrong, it does not represent the accepted view in physics today.
 
  • #36
Michael F. Dmitriyev said:
X-ray and Gamma both being "photon" aren’t massless.

http://www.defra.gov.uk/environment/statistics/radioact/alldefs.htm
Gamma ray
a discrete quantity of electromagnetic energy, without mass or charge, emitted by a radionuclide. They cannot penetrate lead or a large thickness of concrete. See x-ray.
X-ray
a discrete quantity of electromagnetic energy, without mass or charge, emitted by an x-ray machine. See gamma-ray.

These are definitions pulled from one of many web sites.

An electron has a mass of 0.5MeV which is in the range of gamma rays. Just because the energy of the gamma ray is quoted as being 0.5MeV doesn't give it mass, just similar energy.

If any photon had non zero rest mass, then it's relativistic mass would be infinite.
 
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  • #37
sol2 said:
Would this be a be a fair assumption?

The assumption is fair only if we take spacetime into consideration. The time in spacetime is one dimensional and it has two directions. The space in spacetime can be contracted to one dimensional and it also has two degrees of freedom.
 
  • #38
Antonio Lao said:
The assumption is fair only if we take spacetime into consideration. The time in spacetime is one dimensional and it has two directions. The space in spacetime can be contracted to one dimensional and it also has two degrees of freedom.

I mentioned the Friedmann equation and the curvature parameters.

Include in this http://superstringtheory.com/cosmo/cosmo21.html.

There are a couple of models here for consideration when we include time.

Dirac Matrices come to mind, as well as listing the two other references for a dynamical realization.

Omega =1?

Does this seem consistent?
 
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  • #39
sol2,

I am starting a thread entitled: Inside and Outside Spacetime.

If omega is greater than 1 then, I think, even a vantage point outside of spacetime will not be able to see inside the universe.

If we can make the assumption that each elementary particle is a microcosmos and each has its own omega, this omega cannot be greater than 1 since we can derive properties of mass, charge, spin, and magnetic dipole moment.
 
  • #40
Time is, we are. Things exists in what is.
 
  • #41
It is all circular motion. Time can be measured in its different realtivity according to one place in the universe if and only if, the universe is spherical that's just as crazy as saying that Jupiter has a storm the size of Earth on it. the universe must be spinning also and that time can be measured from this point and possible along the axis.
 
  • #42
AWolf said:
These are definitions pulled from one of many web sites.

An electron has a mass of 0.5MeV which is in the range of gamma rays. Just because the energy of the gamma ray is quoted as being 0.5MeV doesn't give it mass, just similar energy.

If any photon had non zero rest mass, then it's relativistic mass would be infinite.
Does mass-energy relation false today? I mean E=mc^2.
If no, then:
“ Two objects having equal energy would have equal mass”.
It’s right.
 
  • #43
But any object with rest mass would have infinite mass when traveling at lightspeed. What AWolf said was that a photon has no rest mass.
 
  • #44
Equation To Find Number Of Dimensions

May,20,2004

A GENERALIZED EQUATION TO CALCULATE NUMBER OF DIMENSIONS

Sometime ago Dr.Syed Ameen had derived an equation,(see http://www.superstringtheory.com,postings , which can be used as a generalized equation to calculate the number of dimensions for any phenomenon or event or situation.The equation involves the tiotal number of VARIABLES( V ),in any natural phenomenon or event or happening.The number of DIMENSIONS( D ),are always less by one( 1 ).
Therefore the generalized equation is:

D = V - 1

To test the validity of this Dr.Ameen's equation to calculate total number of Dimensions,for example take Gas law,and it will prove to be right.In the same way this can be applied to any other phenomenon.

Dr.Syed Ameen( Ph.D. )
 
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  • #45
LURCH said:
But any object with rest mass would have infinite mass when traveling at lightspeed. What AWolf said was that a photon has no rest mass.
There are no objects with rest mass traveling at lightspeed.
 

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