If Earth responds to civilizations 6 billion light years away, how long will it take for them to rec

First of all, humanity has not communicated with the long extraterrestrial civilization at this stage. 6 billion light-years far beyond the scope of the Milky Way, the distance between data signals spread so far may greatly attenuate the coefficient (the basic law of inverse proportionality of square meters), with the current high and new technology of human beings, not to mention the alien civilizations of the alien galaxy, even the alien civilizations in the galaxy send data signals to mankind, and everyone cannot reply to them. Therefore, the ** below is purely based on the perspective of basic theory.

If the universe is static data, then if we reply to extraterrestrial civilizations 6 billion light-years away, they may receive data signals from humans 6 billion light-years later. Since the medium of the data signal is radio waves, and their rapid propagation in the vacuum pump is the speed of light, the time it takes to spread a distance of 6 billion light-years is 6 billion light-years. This means that after an alien civilization 6 billion light-years away sends a signal to Earth, they will have to wait 12 billion light-years before they can receive a human response.

But in reality, the universe has expanded, pushing the long extragalactic galaxies farther and farther away from the Milky Way, so the problem is getting more and more complicated. At large scales, the expansion of the universe is very uniform, and the Hubble parameter can account for the expansion rate of the universe.

Here, the Hubble parameter is 70 (kms) mpc, which shows that for every 3.26 million light-years (1 million parsecs) of spacing, the rate at which extragalactic galaxies avoid the Milky Way increases by 70 kms, which means that planets 6 billion light-years away are rapidly avoiding the Milky Way at a rate of more than 10,000 km-seconds (43% of the speed of light).

In addition, the Hubble parameter is not a parameter in the true sense of the word, it changes over time, because the expansion rate of the universe changes over time. In the beginning, under the effect of attraction, the universe was expanding at a reduced rate. By 5 billion light years ago, when dark energy took possession of the core, the universe gradually expanded faster.

If we receive a data signal that spreads 6 billion light-years in the universe, then, with the expansion of the universe, the distance between this signal source and the Milky Way at this stage may be 7.6 billion light-years, and 6 billion light-years is only the distance between the lines of light. After human beings send signals to extraterrestrial civilizations, with the change of time, the rate at which the planets to which extraterrestrial civilizations belong will become faster and faster, which will prompt the dispersion of data signals to extraterrestrial civilizations will be far more than 7.6 billion light-years. According to the Friedman equation, the data signal needs to be propagated at a distance of 10.6 billion light-years, so it needs to take 10.6 billion light-years, not 6 billion light-years or 7.6 billion light-years.

As a result, extraterrestrial civilizations would need 16.6 billion light-years faster after signaling until humans respond.

It takes decades for them to receive signals from the Earth, after all, the distance is very far, and it is really difficult to get a response from the other party.

It takes a long time, because it takes a long time for them to send a message, and we send it back, and when they get it, it takes twice as long.

It takes 12 billion light-years, and the information received from the earth is 12 billion light-years, so the other party should also receive 12 billion light-years.

The received signal takes about 6 billion light-years, which is also a relatively long time, and it can also reflect the distance between the Earth and other planets.

It takes 6 billion light years, which is quite a long time, and basically there is no reply from the other party.

It will take about 12 billion years to wait, which is a very long time, and it has a great impact, so it is difficult to wait.

The fastest time it will take is 6 billion years. Because the fastest speed in the world is the speed of light. 6 billion light-years is 6 billion years at the speed of light. The speed of the signal will be a little slower than the speed of light, so it will take longer.

Light-years refers to the distance traveled by light in a year, and 6 billion light-years means that light needs to travel for 6 billion years, that is, it takes us 6 billion years to receive the information sent from there.