How to Detect Extra Dimensions | Space Time

  • Published on Oct 3, 2018
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    On this Space Time Journal Club we look at how gravitational waves can be used to search for extra dimensions of space!
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    "Limits on the number of spacetime dimensions from GW170817"
    Pardo, Fishbach, Holz & Spergel 2018

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Comments • 3 112

  • HerbalTerrorist420
    HerbalTerrorist420 6 hours ago

    Best way to detect an extra dimension is to smoke some dmt. Imo.

  • tecums3h
    tecums3h Day ago

    I'm waiting for Dr. Steven Strange to start doing his sparkly jazz hands ninja moves.

  • turbocarte
    turbocarte 4 days ago


  • WestOfEarth
    WestOfEarth 7 days ago

    Having read only the abstract, a few questions arise. Couldn't the models being used be wrong themselves? When the authors speak of gravity 'leaking' into 4-d space, what happens if instead gravity is 'leaking' into 3-d space from 4-d space? Does recent studies hinting that the Hubble constant may not be constant over time affect the results? Call me skeptical, especially with only 1 study to offer as evidence.

  • Johnathan Sirko
    Johnathan Sirko 8 days ago

    Maybe next time don't "tweak the theory so much" bud, moderation is everything.

  • Seek The light
    Seek The light 9 days ago +1

    Oh you can also go to these diemensions, it’s called DMT have fun everyone ☺️

  • Gambeir Bay
    Gambeir Bay 9 days ago

    A Ferrocell Lens clearly shows that a magnets' magnetic shape is manifesting it's theoretical self in #3D. It does not manifest itself in 4D. Hypothetical mathematical abstractions do make reality true by virtue of their correctness. So instead what we actually have is a validation of the existence of the Aether and as a hyperspatial medium which is #3 dimensional and not 4 Dimensional.

    Until proven otherwise by physical evidence there are no other dimensions. There is only a medium which is itself a part of the EM field, which is hyperspatial and hypervelocity, such that a magnetic field appears as solidified yet fluid material. There is absolutely no evidence whatsoever for other realities. It's a hypothesis based on mathematical abstractions and to conclude they exist without evidence, and to then pretend they exist and to market such is reprehensible.

  • Donald Smith
    Donald Smith 15 days ago

    Thank you for this series, hope you're making a good buck and finding satisfaction.

  • c704710
    c704710 16 days ago

    If there are other dimensions and gravity and radiation from our 3+1 do not reach them, then a black hole can be safely observed up close, even from behind the event horizon. However, lack of observable gravety and radiation would greatly limit what is observable. Whatever is left to observe would be whole or part of the missing information of the paradox.

  • young chazo
    young chazo 16 days ago +1

    In theory, couldn’t an extra-dimensional “being” be right next to you at any moment? You would never be able to tell. Kind of creepy.

  • studio Já Games
    studio Já Games 18 days ago

    4+1 dimension is cool, but what about 3+2, or 4+2 dimesion?

  • Dj Death
    Dj Death 18 days ago

    the fact that we have gravity proves that the universe is not infinite

  • Amanda Ouellet
    Amanda Ouellet 20 days ago

    There are just as many realities as there is people. Each person at a different dimension of consciousness.

  • Toughen Up, Fluffy
    Toughen Up, Fluffy 21 day ago


  • Toughen Up, Fluffy
    Toughen Up, Fluffy 21 day ago +1

    No, we are not living in a science fiction future, we are living in a science fact present.

  • Toughen Up, Fluffy
    Toughen Up, Fluffy 21 day ago

    The theory with the biggest balls wins.

  • Joseph Malone
    Joseph Malone 23 days ago +2

    Is there something harder? This is not complicated enough.

  • Alexander Nikolaevich
    Alexander Nikolaevich 27 days ago

    Could be possible what we used to call time in fact is extra dimension to space ?

  • Zes
    Zes 29 days ago

    no such thing as mindbx or not, any b infninx interesx no matter what, no uch thing as unifx or not, doesn't matter, no sadx

  • Jason Hagar
    Jason Hagar Month ago

    How can I travel to another dimension where it's May 22nd, 1995 and I'm in 6th grade again.

  • Helder De Almeida
    Helder De Almeida Month ago

    Why don't some scientists make a new theory of everything without thinking of what we know just start from the beginning

  • Bhavesh Mahale
    Bhavesh Mahale Month ago

    Do you think, black holes might be causing Universe to expand? Whatever matter they suck in is churned up into smaller invisible particles and this particles might be occupying extra volume in invisible dimensions of space. Forcing the other visible dimensions to expand. The same particles might also appear like dark energy in space!

    • Bhavesh Mahale
      Bhavesh Mahale Month ago

      @alistair watt In short, what food we eat is churned up inside the stomach and some portion of that food helps our body to grow and some is ejected. In the same way, black holes are like mouth and stomach, food is the matter and light, and lower dimensions represent body, excreted matter is dark energy. And expansion of space is growth of the body. Universe is getting fatter because of dark energy.

    • Bhavesh Mahale
      Bhavesh Mahale Month ago

      @alistair watt black hole throws radiation under the carpet of space time. Where that radiation interacts with lower curled up dimensions, which then emmit the dark energy, which we can observe from higher dimensions. That same energy is accelerating expansion of space. Dark energy emerged when lower curled up dimensions couldn't hold that excess amount of energy and they started to emmit dark energy as a result, universe entered into second phase where it started expand faster than before!

    • alistair watt
      alistair watt Month ago

      the expansion of the universe seems to be accelerating due to dark energy.

  • Corvid Moon
    Corvid Moon Month ago +1

    "But a god can exist in other spacial dimensions, right?" According to the nature of gravitational waves? Hell no. If no other spacial dimensions exist (and we've observed that they don't), then nothing can exist in something that doesn't exist.

    • alistair watt
      alistair watt Month ago +1

      I think religious people will one day run out of gaps to hide their God in.

  • John Broomhead
    John Broomhead Month ago +1

    The earth is a cube

  • Jason McMurry
    Jason McMurry Month ago

    If the gravitational waves were observed 1.7 seconds prior to the gamma rays....then does that mean gravity travels faster than light? I understang that gravity affects light...but can it outrun it?
    Or did the waves just preceed the rays due to how/when they were created?

  • John Johnson
    John Johnson Month ago +1

    I know about the Fifth Dimension. I love most of their songs.

  • Adam Gray
    Adam Gray Month ago +2

    4th spatial dimension: *exists*
    Gravity: "aight imma head out"

  • Allen Marples
    Allen Marples Month ago +1

    there is no definition of other dimensions

    • alistair watt
      alistair watt Month ago

      yea, from what I understand, the extra dimensions just seem to be theoretical possibilities that have yet to be proved. I don't have a degree in physics (I studied neuroscience) so I really don't have a very good understanding of advanced physics though, so I could be wrong.

  • Konrad Swart
    Konrad Swart Month ago

    I think we count the dimensions wrong. There are at least 6 dimensions we already should be aware of. 3 displacement dimensions, and 3 rotational dimensions. So the number of dimensions of space has is already 6. I do not count time as a dimension, because it is only one-way: from past to future.

    You might argue, that a point cannot be rotated. But, then again, there exist, in reality no objects that are points. Not even the electron. Assuming that an electron is a point leads to an infinity. The electric potential or the electric field at very close distances would blow up to infinity. Therefore there is something wrong with our picture of the electron as a point being situated somewhere in an orbital of an atom, moving, accelerating even, but _not_ radiating.

    The best explanation I would think of is that these orbitals around the atom _are_ the electrons, since the detection of electrons always happens in one way or another when they collide with other electrons. So the 'flashes' on screens that detect an electron are of the same magnitude as those orbitals.

  • Tony Lopezz
    Tony Lopezz Month ago

    Fukn boring af bro..can't believe I watched all this BS

    • alistair watt
      alistair watt Month ago

      if science had never existed, then computers would have never come into existence and you would have never even been able to write that comment.

  • Sean Nitte
    Sean Nitte Month ago

    Can you express gravity as a reduction in a dark energy constant?

  • pinpoint45
    pinpoint45 Month ago

    i dont really understand physics, my 2 bit theory is that gravity is an effect of a higher dimensional field on the fields of what we consider matter and energy. so like on a higher dimension, the known universe past and future, is moving relative to something. and that something is what causes gravity, and the causality speed limit.

  • dragon ball talk
    dragon ball talk Month ago +1

    More images less this man

  • medexamtoolsdotcom
    medexamtoolsdotcom Month ago +3

    It's so lame how you keep trying to find an excuse to say "spacetime" and then say it differently in the last sentence.

    • JiveDadson
      JiveDadson Month ago +1

      It is annoying, but they won't stop. Cringe and bear it.

  • OpportunisticHunter

    I never seen PBS go completely full of shit! That is not even a theorized form of detecting extra-dimensions...!!! It is all just a bunch of bullshit!!!

  • OpportunisticHunter

    @PBS Space Time But if extra-dimensions are predicted and theorized to be extremely small ...why then are you trying to detect it though a huge wave from a huge explosion from huge stars far on the Cosmos??

    • Cosmic Landscape
      Cosmic Landscape Month ago +1

      OpportunisticHunter Listen what he said you idiot. It is about macroscopic extra dimensions

  • White Thread
    White Thread Month ago

    Simple enough

  • Jari Haukilahti
    Jari Haukilahti Month ago

    So a gravitional wave dont hit the overlying or underlying branes ? Is not the amplitude big enough ? And shouldnt this create something is it actaully hit a neighbouring brane or does it steal energy ?

  • Dumb Ass
    Dumb Ass Month ago

    Smoke a joint.

  • Maverick Black Belt Academy

    Branes, String "theory", and extra dimensions are just a flight of fancy. If you think there is "dark matter" it only means our equations need reworking, not that some mysterious matter that has only one property of matter exists.
    Quantum physicists can repeatedly demonstrate the bizarre quantum interactions.
    Cosmologists can predict the period of exoplanets.
    However, when math gets too difficult for some physicists they just make things up like dark matter and extra dimensions.
    Yes, which is more likely, that the universe has a secret dimension, or that a human being doesn't have the right idea and/or calculations?
    Hell, all I am asking for is a demonstration that such things are real.
    Everyone knows that gravity becomes weaker as it spreads because the angels cannot hold so many things very strongly. :P

    • Maverick Black Belt Academy
      Maverick Black Belt Academy Month ago

      @Cosmic Landscape Glad you hold the possibility that the calculations can be right while the assertion that are String and dimensions can be wrong. This raises the question though, and excuse my language but how the fuck would you propose to know that either of those are true?

    • Cosmic Landscape
      Cosmic Landscape Month ago

      Maverick Black Belt Academy they do make predictions. Also useful in calculations and in understanding nature even if wrong

    • Maverick Black Belt Academy
      Maverick Black Belt Academy Month ago

      @Cosmic Landscape
      You need to get your money back from your university. They have misinformed you about what science is. See, because hypotheses make predictions. Extra dimensions and String Wishing don't do any suchthing.

    • Maverick Black Belt Academy
      Maverick Black Belt Academy Month ago

      No, you just don't understand what science and math are. You think they exist, aparently, and are perfect and true by virtue of.... whatever your bias is based on. People should really try interacting with reality before positing that we can know things are real by wishing real hard.

    • Cosmic Landscape
      Cosmic Landscape Month ago

      Maverick Black Belt Academy it is called a hypothesis 🤦🏻‍♂️ that’s how science works

  • Maverick Black Belt Academy

    "If you recall, intensity drops off more quickly, the more dimensions you have."
    Demonstrate this, please?

    • Maverick Black Belt Academy
      Maverick Black Belt Academy Month ago

      @OpportunisticHunter Link a video, yo.

    • OpportunisticHunter
      OpportunisticHunter Month ago

      @Maverick Black Belt Academy See Bose-Einstein Condensation. Neutrino OPERA experiment.

    • Maverick Black Belt Academy
      Maverick Black Belt Academy Month ago

      @tomm04471 Thanks, man, but I understand analogies just fine. Analogies are just illustrations. I want to know the evidence for accepting the underlying claim. Otherwise it's just bald assertion taken on faith. Science isn't a religion or a faith. The dimensions have to be demonstrated to exist.

    • tomm04471
      tomm04471 Month ago

      If I understood correctly, an analogy would be this; a drop makes a ripple in water. Each dimension would absorb more of the energy required to continue said ripple

  • Pink Droid
    Pink Droid Month ago

    Surprise surprise, a 3D event produced 3D results...

  • Padawan Atodon
    Padawan Atodon Month ago +3

    “String theorists are okay...for now.”

  • RubelliteFae
    RubelliteFae Month ago

    Off topic, but why do we assume 3+1D instead of 3+2D where the extra temporal dimension represents the plane of "now" across all universes in the Many Worlds' multiverse?

  • RubelliteFae
    RubelliteFae Month ago

    Doesn't this assume the light is traveling through pure vacuum? Is that a safe assumption? That is, how do we know there isn't a lot of dust between us and the source?

  • Akanaro O.O
    Akanaro O.O Month ago

    I've never felt comfortable with this mambo jumbo about extra dimensions anyway. They keep telling us that a four dimensional object, interacting with our three dimensional world, would just pop into existence as a three dimensional shape. Fair enough. Can you show me such a shape? Can you point to any planet, star or human who was minding its own business when it suddenly bumped into a mysterious shape that appeared out of nowhere? No? It never happened anywhere in the universe in 13.8 billion years? Of course people will go, "yeah but you can't see it dude". Why not? Does matter behave any different because it comes from a fourth dimension? If I stick a cube into a piece of paper the 2D people living on that paper is dam well gonna notice it. Right?

  • Henry McCarty
    Henry McCarty Month ago


  • Karsten Johansson
    Karsten Johansson Month ago +1

    If gravity is a wave (versus a velocity against something in a higher dimension), why can't they cancel out like every other wave we are aware of?

  • Matt Johns
    Matt Johns Month ago

    I been to another dimension...thanks dmt

  • Rajneesh Kumar
    Rajneesh Kumar Month ago

    Someone need to change this anchor because his voice is blurry and delusive....and he is not doing anything to please bring people with more clear voice ...thank you for the contents though...

    • alistair watt
      alistair watt Month ago

      I don't think they should ever change this anchor. He does a very good job.

    • Ivan Sole
      Ivan Sole Month ago +1

      I think you are mistaken my friend.

  • Nikolay Cherednychenko

    You inspire me!

  • Boop
    Boop 2 months ago

    Before i watch this try drugs. It opens your eyes more than you think but can tear your life away really fast. Beware

  • Ever Hernandez
    Ever Hernandez 2 months ago

    great show this is what I think the lack of black matter is black matter

  • Thomas Stevenson
    Thomas Stevenson 2 months ago

    What if gravity was the fabric of space itself? Could that explain why gravity is weak?

    • RubelliteFae
      RubelliteFae Month ago

      I think it's worth exploring in this direction.
      We can think of gravity as the geometry of spacetime as Einstein did. In this view spacetime bends where there is mass. This bending attracts more mass. But, we don't understand why "dark matter" bends spacetime without being visible. So, a thought I've had similar to your own is that "dark matter" is the "natural" shape of spacetime before any "normal matter" has influenced its geometry.
      Unfortunately I'm not schooled enough to run farther with this thought.
      That said, no, geometry wouldn't explain gravity's weakness.

  • Skip Michael
    Skip Michael 2 months ago

    Gravity waves is made up of expended protons. When struck by other moving protons they take on their properties and speed up.

  • Fernando Montes De Oca
    Fernando Montes De Oca 2 months ago

    How do we know the extra dimensions base on Space? All is Emotions right! Energy in Motion! & How we determine the Speed Variables of these Emotions base on what Time (Light) Ether Vacuum and Space! Dark Energy Interactive algorithm and Atomic Clock Needed! Plus Galaxy Position System Entangled (Time Bubbles)

  • I.C.G Flying Channel
    I.C.G Flying Channel 2 months ago

    But you calculate the initial gravity based on the mass you see on 3D not in 4D. You are assuming that all there is is what you can measure...

  • R B
    R B 2 months ago

    I tried

  • N. Holbrook
    N. Holbrook 2 months ago

    Sounds like the theory is broken. Gravity is probably an emergent property of objects that exist so its properties don't need to mirror the atomic forces or even just EM.

  • M Al
    M Al 2 months ago +2


    • M Al
      M Al 10 days ago

      @Jairod Duarte OFFCOURSE IT IS.. 🙏🙏🙏

    • Jairod Duarte
      Jairod Duarte 10 days ago

      actually it is a Frequency = sound and light