 1. nikita_kotov says:

From the point of view of physics, any material body moves in four-dimensional space-time at the speed of light. This velocity is made up of the velocities in each of the four dimensions. The faster you move in the spatial dimensions, the slower you move in the temporal. To move backwards in the time dimension, you need to move faster than the speed of light in the spatial dimensions. And this requires infinite energy for any real mass. This makes it difficult to send information back. But if we assume that there is an imaginary mass, then bodies with an imaginary mass can move in this way, in fact, hypothetical tachyons are arranged in this way.

2. evgeny_kandzyuba says:

According to modern scientific perception, it is generally accepted that information is also energy.

This follows from the fact that to describe the degree of chaos, for example, for thermodynamic systems, the concept of entropy is used and the logarithmic dependence for it was derived by Boltzmann in the 19th century.

For information theory, the concept of entropy was introduced by Shannon in the mid-20th century. When analyzing these two formulas, it becomes clear that they have the same nature, since the difference is reduced only to a coefficient, read the Boltzmann constant, which is in the equation of thermodynamic entropy. Everything else is identical!

And if so, then we can say that the degree of chaos (entropy) is an indicator of awareness about the state of the system.

Given that entropy can only increase in the universe without external influence, scientists have come to understand the unidirectional arrow of time.

But from the point of view of pure mathematics, it is worth recognizing that the equations are invertible provided that complex values are present in the solution.

Example-expressing the difference of squares as products:

and how to decompose the sum of squares?

Yes, by introducing a complex unit, we can also decompose the sums of squares into a product. What did I do? I added another complex axis to the two real ones. Or moved to the dimension of a higher-order space.

So, remaining in the standard understanding of the four-dimensional universe, we have many limitations. One of the most famous, as an example from school: you can not divide by zero, which means that two numbers that are not equal to zero in the product of zero will never give. But in a complex space, this ceases to be a dogma.

Here is an example of a matrix analysis implementation of what zero divisors can look like.

The second problem on a fundamental level is transcendental numbers.

Everyone knows the Pythagorean theorem, but asking the question: what is the diagonal of a square with a side of one, you will never get an EXACT answer. Analytically, the answer will look like this:

(and an approximate value up to 20 decimal places ):

No matter how accurately we calculate the result, when squaring, we will never get a two. What does this mean? That in our world the square of transcendental numbers has a physical meaning, but the transcendental number itself has no meaning for us.

Refinements of more than 37 characters do not make sense, because on such scales the quantum of the dimension of space is determined by the Planck constant

It follows from the above that the mathematically obtained solutions for the reverse direction of the arrow of time are valid, but for their physical implementation it is necessary to expand our understanding of nature (or Physics in Greek).

Given also that energy has the equivalent of mass, information to be transmitted back in time must have negative energy and negative mass.

What is it in our world? Earth science has no idea yet.

If we assume that Mathematics is the language of Physics, then not all mathematical constructions are found in the form of physical processes. The same applies to the transmission of information in the negative direction of the arrow of time.

Therefore, from the point of view of modern physics, there is no understanding of how to make this possible.

3. nikita_galichev says:

We must first understand what time is.
How do we know that time has intervened?
Then, when there were some changes, while at any point in the universe something changed. And something changes here and now, and everything else is your memories. Therefore, time is always a true characteristic. So far, the laws of physics do not know how to mirror and do not reflect changes.
Past and future are concepts introduced by the human mind to conveniently form causal relationships in the brain.
Conclusion: to transmit information to the future, you only need to save it in the present. And it will be possible to transmit to the past only when all the changes in the universe go in a mirror (reverse) order, there is not a single premise on which this could happen.

4. dmitry_runables says:

modern physics strives by leaps and bounds to prove the fact of the directed movement of time, and at the same time directed in the usual direction ..

so, to answer your question (although I'm not a physicist), we can say that sending information to the past is hindered by physics ' desire.

at the sci-pop level, advanced views of physicists are presented in the film “argument “(tenet), which seems to solve the problem of knowing the future without traveling to the future, and transmitting data to the past without traveling to it.

if we consider philosophy (far from physics), then changing information about the past is a cool feature of Chinese philosophy (“but this is not what barbarians think”).. there, time is not considered unidirectionally, and therefore it is allowed to change the facts of the past from the present (this has nothing to do with falsification or deception, but more like cones-see below), although this is seen as an extremely rare and extreme measure .. The “butterfly effect” has not been canceled.

there are also weird sectarian theories , such as” transurfing reality”, where it is argued that a person can choose any version of the past, including the one where he would send information to the past, if possible.

it is also necessary to represent the space of time not as a straight line (past-future), but still add a space of options, even hypothetical, all sorts of branches and versions of what is happening .. at least in order to get used to a broad understanding of time.

at the very least, a quantum cone will also work —

so, send as much as you can .. and suddenly it will work ..

5. not_chu_rui says:

Igor Ryabushkin, a person accepts any information from the past, but transmits it to the future. This is a law of nature, that is, physics (Greek: φύσις — “nature”). Quantitative and qualitative changes(movement) of matter are perceived by a person as information coming from the past. If the object is nearby, the time for transmitting information is insignificant, you can say an instant, and if the information is from distant galaxies – millions of light-years. But in both cases, the information comes from the past. And the transfer of information by a person is carried out purposefully, using the same changes in material objects, and is directed to the future. And the recipient of the information will receive it after some time, already from the past. This is the logic of nature-physics, unless of course you fall into relativism, which operates not with real physical (natural) objects and phenomena, but with fictional (abstract) mathematical concepts.