The Science of Time Explained by Brian Greene

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Theoretical physicist, mathematician, and string theorist Brian Greene explains the science of time. As a general definition, time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. Brian Greene simplifies the concept of time so we can have a better understanding of it.

In general relativity, the physical nature of time is addressed with respect to events in spacetime. For example: The collision of two particles, the explosion of a supernova, or the arrival of a rocket ship.

Brian Greene also explains if its possible to time travel. One of the most frequent questions people wonder when thinking about time is whether its physically possible to go back in time. But a central problem with time travel to the past is the violation of causality.

As for going back in time, it is in direct violation of causality. Giving rise to the possibility of a temporal paradox. Some interpretations of time travel resolve this by accepting the possibility of travel between branch points, parallel realities, or universes.

#bgreene #sciencetime #timetravel

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22 thoughts on “The Science of Time Explained by Brian Greene

  1. So, what if you program the ship to go outside the gravitation field and set it for the time/space that would equal 1 million years, to the day, in the future, and your ship never comes back to the 'present' because the Earth is irradiated by then (from nuclear war)? Then, those in the present never learn how their behavior resulted in their own self-annihilation because you never returned. Therefore, nothing can be corrected to prevent the our future annihilation other than our own inner evolution.

  2. A sincere comment: Law of nature is supposed to be discovered but not to create. Superposition principle, relativity theories, Quantum electrodynamics, Anti-matter, Blackhole, and others were created. If we keep teaching those fictitious principles and theories well be more harmful than beneficial to our science and to our students. My question is that would you want your children and grandchildren to continuingly learning theses fantasy principles and theories that was created but not discovered. Please watch the attached YouTube link and think about it.

  3. Hello, my name is Dylan. I go to Endeavor Charter School in Watertown, Wisconsin. Endeavor is a project-based school, we use research to gather information on the topic. I am doing research on time and how humans experience it for a school project. I was wondering if you would be willing to answer a few questions to help me in my research.

  4. I think a twilight episode showed a guy stepping through prism and out the other side he was at 1 degree difference. He looked at his watch and it was the same but nobody could see him. 😁

  5. Psalm 104:2 NIV — The LORD wraps himself in light as with a garment; he stretches out the heavens like a tent.
    The Bible says that God stretches the heavens like a fabric…which is interestingly what we call space.( "Fabric of spacetime").
    I believe time is Him literally stretching that fabric. In our ant-like perception, time exists because of the red-shift it causes. It explains gravity, wormholes and so much more.
    Try opening your mind and looking at it from that perspective and see what happens.

  6. Time doesn't pass. Time just IS. And we travel through it. Everything that has happened, or will ever happen already has, is, or will happen.

  7. Imagine this massive universe is in a box. Imagine billions and billions of galaxies are all inside a massive box.

    Now think of TIME. Everything in the box is transitioning from one state to another based on time information. Every component in the box, the atoms, the photon, dark energy, dark matter, fundamental subatomic particles, energy, gravity, genetics, the laws of physics and the laws of chemistry are all interacting with time.

    Every atom has time within it, dark matter, dark energy uses time, genetics uses time and every other fundamental component uses time. Every component of this universe depends on this time information to function.

    As every component of this massive universe is interacting with time, the source of time information cannot originate from within this box. As every component inside the box is changing as per the time information, the source of time information has to come from outside the box. The force of time is proof that there is control coming from outside this universe.

  8. A space ship fast in space gets to time travel faster into the future of the rest of the universe
    because its time rate is much slower… the differential of space ship slow time and the rest going ahead in fast time
    is the only time travel.

  9. If you’re not a born again Christian then chances are that you’ll be unable to place your right palm on the KJV and say these words once only-> I refuse to be deceived by the devil.

    Rev.12:9 The devil deceives the whole world.



  10. NO ONE can show me time outside of the BRAIN'S ABILITY to remember and anticipate. In math, time is just a sequence marker to sequence the changes that occur. Where it was and where it will be don't mean anything, and you cannot show that to me. You can mark changes with Oreo cookies. I would like that better.

  11. Not one mention of entropy? That's somewhat surprising. Wheeler's quote is absolutely wonderful and captures one characteristic of Time. But if we look at a photon traveling billions of years through empty space, everything in the lifetime of that photon actually DOES happen at once, because, traveling at the speed of light means the photon's internal clock moves at a rate of zero. Much of the conundrum of Time can be solved by accepting that Time is a fourth spatial dimension. Now, the usual argument is that the Inverse Square Law (ISL) prohibits that because gravity and light would diminish by the inverse cube if time was a spatial dimension. However, the subject of such ISL arguments is either a graviton or a photon which does not travel through this dimension as we see from everything happening at once for the photon (and the graviton presumably also moves at c). Therefore, the ISL is measured as expected for 3 dimensions, since no time passes for those particles and there is a fixed relationship between Space and Time, those particles traveling at c, do not pass through the 4th spatial dimension at all and would not display dispersion at an inverse cube rate . For this to work, Time has to be a dynamic field as opposed to a static field of the other 3 dimensions. That isn't a problem if we examine the causality and hierarchy of the dimensions themselves (but that's another story in itself). But what about sound, you may ask? The ISL holds for sound because the source, the medium, and the receiver are all moving through time at the same rate, traveling together as it were. It would be the same reason that sound inside of an airplane isn't distorted by the speed of the airplane. Accepting Time as a 4th spatial dimension can free up a much better analysis of the topology of the Universe and as Rocky Kolb says, in cosmology "topology is everything".

  12. I am surprised Brian not know "what time is " …and nobody know what's ….let me enlighten you all …TIME IS A DIMENSION …and doesn't only go forward…time stop , goes forward or backwards…space affect times … energy affect times and speed affect time ..Jesus even the human mind affect time!

  13. in the beginning there was no distance and there was no time. After the Big Bang space expanded and there was growing distance. In the same way time expanded and there was growing time. The universe is expanding in space and in time Whether you choose to measure it or not, it is expanding. So seconds, days, years, centuries are just tools we use to measure it.


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