There’s a Loophole in One of the Most Important Laws of Physics
Articles,  Blog

There’s a Loophole in One of the Most Important Laws of Physics

[♪ INTRO] When you study physics, they teach you a bunch
of rules. Things like how you can’t create energy,
you can’t travel faster than light — it’s like, stop telling me what to do, man! These rules are helpful, though, because they
give you a framework for how the universe works. Like, no matter how complicated things get,
at least it’s not a lawless wasteland out there. Except, there is one law of physics that’s
fundamentally breakable, even though scientists don’t usually treat it that way: the second
law of thermodynamics. To put it simply, this law says that a system
will never become more orderly on its own. The amount of disorder will always increase
or stay the same. It’s a cornerstone of physics, and it tells
us how everything from car engines to galaxies should behave. But if you look closely at it, you can see
that it’s a law that was made to be broken. And for the world of nanotechnology, that
could lead to unexpected consequences. Although you might have a pretty intuitive
idea of what disorder is — like, if you’ve looked at your sibling’s bedroom recently
— scientists have a more specific way of thinking about it. They measure the amount of disorder with a
concept called entropy. Entropy can be considered a measure of randomness
— or how orderly a bunch of particles are — but it can also be considered the amount
of energy that’s unavailable to do work. Like, imagine running a car engine. No matter what you do, the engine will always
turn some amount of fuel into waste, like heat. This is unavailable energy, because it can’t
be used to make your car go forward. According to the second law of thermodynamics,
the longer you run your car, the more unusable energy you’ll get. In other words, the more entropy will increase. This observation is actually what led to the
discovery of the second law in the first place — although it was discovered in the 1800s,
so it was about steam engines, not cars. And today, we know that concept applies everywhere. It’s why engineers still can’t make a
perfectly efficient machine, and — on a much larger scale — it’s why the universe
will eventually run out of useable energy. It’s even why the layers of milk and espresso
in your cappuccino will blend together if you leave the cup out long enough. The two liquids might start out all neat and
all artistically separated, but they’ll eventually become more random and will mix. Essentially, the second law says that entropy
will never decrease on its own. Even if you do create order in one system,
you’ll always create disorder elsewhere, like by generating heat. But for as confident as this law sounds, it
isn’t bulletproof. If you look closely at why the second law
exists, you start to realize that it has a pretty big loophole. At the most basic level, the second law is
true because molecules move around randomly, due to their thermal energy. And they’re equally likely to move in any
direction. Ultimately, this means there are way more
opportunities for particles to end up disordered than ordered, so disorder is more likely to
increase. Think about that cappuccino again. There are probably around a few septillion
molecules — that’s a one followed by 24 zeroes — in the drink. And there are only a few ways those molecules
can be arranged so that all of the milk is on one side, and all of the espresso is on
the other. So assuming one arrangement is just as likely
as any other, the odds of your cappuccino getting more orderly are really, really tiny. But the thing is… “really, really tiny”
is not quite impossible. It could happen. Of course, the odds of this happening for
a cup of coffee are so slim that they’re kind of ridiculous, and they don’t mean
much to physicists. That’s why the second law can so confidently
say that the entropy of a system never decreases on its own. But in reality, that law is just a statement
about the statistics of particle motion. In other words, it’s so likely for entropy
to increase — or at least stay the same — that we can functionally say it does it
all the time. Except, for small systems, we can’t assume
that. And by “small”, I don’t only mean systems
of, like, two atoms. In recent decades, scientists have found that
in systems with up to 100 particles, it’s not too unlikely for random chance to decrease
entropy, just for a little bit. One of the biggest experiments came in 2002,
when Australian researchers published evidence for entropy decreasing in a collection of
micrometer-sized beads suspended in water. The random thermal jiggling of water molecules
was constantly pushing the beads around, and for the most part, as expected, the beads
were moved randomly. But then the researchers looked harder. And they found that sometimes, by pure chance,
the beads were pushed in a specific direction, causing them to noticeably speed up. In other words, the beads were turning the
disordered, random heat energy of the water into ordered kinetic energy — energy that
can do work. And it was all for free. This effect only persisted for a few tenths
of a second, but it proves that on a small scale, you can cheat the system, at least
briefly. This wasn’t the only paper to investigate
this idea, either. There was another in 2005 that suggested these
effects might be present in photosynthesis, and a few more from 2013 and 2016 that explored
how this might apply on the quantum level. So it’s something researchers are actively
exploring. While this might sound like a random technical
detail, these studies are actually really significant. Because as nanotechnology continues to develop,
we’re going to be building things like engines and transistors on these smaller and smaller
scales. Realistically, this loophole in the second
law doesn’t mean we’ll be able to make a bunch of tiny, 100% efficient engines or
anything. But it does mean they might sometimes pick
up energy from their environment, or their molecules might move differently than expected. And that’s definitely important for us to
know. The rules developed back in the 1800s will
have to be re-thought to control things at these tiny scales. Otherwise, we might be in for some surprises. Thanks for watching this episode of SciShow! If you want to learn more about the laws of
physics and how they apply to the world around you, you can check out Crash Course Physics,
an amazing series put together by one of our sister channels. You can find it at [♪ OUTRO]


  • Dude

    so, for free energy, I only have to build an "entropy-generator", that somehow ignores all random movevent,
    except the energy that's pushing into the desired direction, to turn it into usable kinetic engery?
    hmmm… I'm too lazy for that.

  • David Jones

    Interesting. But…every progemer knows nothing is truly random, it all comes down to knowing the variables. Statistical mathematics supports this notion. The longer a thing occurs (like the movement of molecules) the more likely a pattern will emerge.

  • Bertrand de Born

    Modern physics is starting to sound like a clown show. The best
    addition to the standard model on light is in Lesseirg papers
    and the mischief of black holes

  • Lexy Starwatcher

    This law is unbreakable…unless it is under these extreme conditions…This is probably more common than you would think. (Energy is not conserved over really really large time frames for example.) Also would imagine over REALLY REALLY long time frames Entropy could drop so much randomly it creates a new universe exactly like this one at the exact moment I typed this…and could do this over and over infinitely. Just me typing at the keyboard….my brain hurts now…

  • Ashmeed Mohammed

    fleck, thats like collecting nutrinos for energy. yes, there is a chance, but its so small and so infrequent, it UNUSABLE. its there, but not enogh to be useful. like paint on the outter surface of a container. it wasnt used, but effectively it was 'used up'

  • Sean Draco

    In distant time humanities descendents will live as machines off the power of random quantum order giving the power to think a sentence a century. Slow super chilled computer people never gonna die!! Maybe, be nice if so.

  • Kyle Cialella

    Look around at nature and how it works. It completely defies all laws of thermal dynamics it's a cute lie to hide free energy from the public. If it was true the universe could not exist….. people that preach about this lie need to stop for a second and really think about what their saying

  • Dark Rainbow

    Randomness has clumps and coincidentally organized spots. Entropy can decrease here and there, but it increases on average.

    That’s what life is.

  • babyrazor

    The real loop hole is that some people get tenure and make a barn load of a salary thinking about this sh*t while the people that produce actual products/services don't make a tenth of that.

  • Jun Acebedo

    Even the law of thermodynamics doesn't escape it's own rule. Atomic sub particles is making this law just a prejudiced human opinion

  • Wu Li

    An autonomous Maxwell's Demon has been created by Finnish physicists, which can sort electrons according to their charges, without expending any energy in the process. An Indian physicist created the first thermal diode that can pump heat from a cold source to a hot one, without expending any energy in the process. Those are both recent advances, but ten years ago someone demonstrated that time can be measured flowing backwards on even macroscopic scales, using a micron sized polystyrene bead suspended in optical tweezers above a heat sink. This women's information is always so consistently outdated and misleading I have to wonder if she's paid to spread disinformation, because the subject is highly classified.

  • Charlie Angkor

    molecules dont move randomly. they move nonrandomly according to laws of collisions conservation of momentum and energy.

  • Adam Rak

    Explaining entropy with order/disorder is very misleading. Some systems have higher entropy when they are ordered. The video does use the good explanation fortunately later, but starts with the misleading one.

  • IKtheVS

    Simply walking down a hill burns physical energy and gives you less gravitational potential… even free will breaks the second law.

  • Chris Russell

    leaves cuppacino out for two weeks and returns to find it has re-separated into far more interesting substances than mere milk, water, and natural oils…

    mmm, lumpy…

    cant help but think back on a quote of teslas " i cant help but feel its all make-believe nonsense"

  • Quinton Craig

    My Dad discovered this phenomenon on a larger scale. He melted a few home made generators he made specifically to test perpetual machines do to the phenomenon.

  • Canis Poetam

    ok ok but wait
    just wait a damn minute.


    Entropy – a gradual decay into disorder
    I'm paraphrasing google.

    I keep hearing science – and scientists –
    insist that the expansion of the universe
    is an example of


    But clearly that's just not so.
    The expansion of the universe
    is an expansion of nothing!
    and before you know it
    nothing is everywhere!

    This is a gradual decay
    into order
    not disorder!

    What could possibly be more orderly
    than the smooth homogeneity
    of nothing!

    And while you may sit there
    and smuggly insist
    that this then represents
    the anarchists dream
    where Nothing Rules
    I will return

    with Nothing!
    For nothing is All!
    All for Nothing!

    And one can never be
    any more orderly
    than that!


  • Marcus Byrd

    Isn't this the idea behind a Boltzmann brain? That a post-heat-death universe has a non-zero chance of particles arranging into a brain for a split second?

  • Patrick Kelly

    You ain't ever leave a latte or macchiato in the fridge for more than two days. Separation, and by what you said, order, increases; entropy decreases.

  • Nigel Depledge

    Colour me sceptical.

    The second law is very easily misinterpreted. For a start, entropy doesn't measure disorder : it measures degrees of freedom. Sometimes these two concepts are as close to exactly the same as makes no difference, but sometimes they are not.

    Second, there's nothing in my understanding of the second law that would prevent a small macroscopic object from borrowing some energy from Brownian motion to apparently do something non-random. But that appearance is deceptive. It's really hard to tell just by observation if something is genuinely random or not. If, for example, you were to write down the results of a thousand coin tosses, you might be surprised to see a sequence of ten consecutive tails; or a sequence of fourteen tosses that alternate heads and tails. But when you work out the probabilities, you find that you should actually be surprised by the absence of such apparent order.

    So I'm reserving judgement on this one.

  • Stephen Furr

    “The law that entropy always increases holds, I think, the supreme position among the laws of Nature. If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations – then so much the worse for Maxwell's equations. If it is found to be contradicted by observation – well, these experimentalists do bungle things sometimes. But if your theory is found to be against the Second Law of Thermodynamics I can give you no hope; there is nothing for it to collapse in deepest humiliation.” – Sir Arthur Eddington

  • I E

    I saw something recently about "liquid crystal" i believe it happens with Cholesterols, where after a certain temperature threshold the molecules in the fluid begin forming parallel arrays. I'm not sure if that breaks the Law but it's interesting. Also on a different note, i believe i saw a sixty symbols video that talked about how energy storage and consolidation happens once an area contains too much random energy

  • Michael Coffey

    Second law of Thermodynamics: Entropy can never decrease
    Microscale Statistical Probability: I'm about to end this man's whole career

  • RKBock

    yeah, no. entropy is not a measure of how orderly something is!!!!!!!!!!!
    entropy is defined as:
    S = k_B * ln( Omega )
    where k_B is the boltzman constant and omega is the amount of states that the system can be in.
    The entropy does not change if the system goes into an ordered state!!!
    it changes if the amount of states it can be in changes.

    you didn't understand the main subject of this video at all. And I doubt that you understood anything that was actually written in the papers.

  • Alex K

    Even with this evidence wouldn't the second law of thermodynamics still pose a threat to the theory of evolution and other theory's like it relating to the origins of the universe? That the molecules in our body (or everything else for that matter) would need some reason to have been put together in the first place.

  • ihrv23

    Didn’t explain entropy very well. I know it’s hard to and I like the approach, but explain how the life came to be, under rules of entropy

  • Shane Mahabirsingh

    So it's possible intelligent design of the universe might be just randomness in the end? Is it safe to say all laws can be broken with enough opportunity?

  • QualcunoDietroUnPC PC

    So this also means that there is a nearly 0% possibility that all the matter in the universe arrange in a single point?

  • Naota Akatsuki

    It also reminds me… Quantum bits also basically dissipate no heat whatsoever… So basically it has no waste energy.. (though a lot of energy is used to maintain other things required for the Quantum Computer to work).. But yeah Qubits are definitely among those exceptions…

  • Josh Fairbanks

    I'm a simpleton, but isn't the while point of the 2nd law that the entropy of the Universe can only increase?

    I mean, sure, it also implies that any process can never lead to a decrease in entropy. So this is a pretty cool deal, but it's not like that much breaking physics

  • Lord Humongus

    "Disorder" is not a property of entropy. This is one of the most misunderstood concepts of thermodynamics. What is implied by entropy is the evening out of temperature, or average kinetic energy per molecule. And the cappucino example is not a good one because the molecules will eventually stratify based on density, although assuming no heat transfer, the temperature would equalize.

  • Mami nathan

    Sometimes I wonder.. All the information out there.. Are they even real? There are contradictions out there. I've always heard entropy increases and it makes sense and now ye claiming it decreases by random fluctuations super rarely in a closed system for a short period. I can picture the probabilities and the possibilities are similar to the boltzmann brain formation? I lack knowledge on this.. all I seek is a true source. So many contradictions..

  • Grant Goldberg

    Cheating the system briefly isn't cheating the system at all because in the longrun entropy always increases. That's like saying because I outrun a marathon runner for a 1/10 of second that I'm faster than him which in my case is of course ridiculous because I'm 70 lbs. overweight. Another analogy would be winning the battle and losing the war. This was a waste of 6 minutes of my life.

  • Nature's Finest

    Does that mean every so often something big can sort of…vanish? Go from some order to suddenly zero. It is just so statistically unlikely that we dont see it.

  • Daniel Stoddard

    Lay person here, does entropy also increase randomly in these small systems above baseline so that the effects of these kinetic coincidences are balanced out en masse? Did the researchers also measure that in their 2002 study?

  • Lin Yen Chin

    WOW!! her spinal alignment is trash!
    She speaks well for a mouth-breather, her speech pattern almost sounds Human aka nostril-breather!!

Leave a Reply

Your email address will not be published. Required fields are marked *