Is there anything smaller than a partical/quark?

[Vince1963]

Well it stands to reason that if the universe started from the "big bang" in the form of a singularity

and all matter was formed from this "singularity", which is all the stars, planets, and galaxies, Then there must be particles smaller than quarks/leptons/boson.... otherwise how could all this matter be compressed down to such a small size?...I understand that in a atom there is an awful lot of space between the nucleus and the orbiting electrons (maybe dark matter)... but this still does not account for all the matter in the universe (which is infinite though a lot smaller in the beginning, apparentlly) to be compressed down to such a small area... To me personally my view is that the big bang never happened, that is unless everything in the universe was created out of something else which we don't understand yet, which could be in the form of "dark energy" and "dark matter" (maybe these are connected in some way) and maybe Black holes are the manufactures of this dark stuff. particles must have been born out of something.... Its like the chicken and egg..

particles must have been born from this dark stuff, because i strongly and personally believe that this dark stuff as been here all the time and all things have come from this.. and maybe science will find out what this dark stuff is one day.But for now i don't believe in the big bang, i do hope they find the answers in my lifetime though and if the big bang happened or not, that would be the icing on the cake for me.

For now we have 12 known particles and maybe scientists at CERNs will discover many more and i personally think they will..who knows these new particles could be if you like "the seeds of creation". Like a flower needs sun light and water to grow, maybe that is simply how the universe started, maybe the dark matter/energy is the catalyst for growth...and the hydrogen was the bi product of this catalyst. I maybe talking rubbish and im sure some of you egg heads will put me straight LOL. I left school with CSE's that is all... But i like to think of myself as a "thinker"... And there is nothing wrong with that.... maybe a dreamer too LOL.

[DrRobin]

Hi,

The gap in the clouds at my house, that is smaller than a quark!

[JamesF]

Well it stands to reason

There's your first mistake, right there. It may well not "stand to reason" if reason is suitably well informed. What you actually mean is "it seems intuitively obvious" which is not the same thing. And macro-scale intuition often doesn't mix with particle physics. Just look at the double slit experiment, for a start.

James

[SamAndrew]

There is quite a bit of evidence to support the big bang, like the cosmic microwave background radiation, the quantities of light elements in the universe, the observed expansion and the distribution and evolution of galaxies.

As I understand it, there was no matter in the early universe, just energy, and as the universe expanded and cooled, matter condensed into existence.

If there is anything smaller than the current elementary particles, I don't think anybody knows yet although I thought electrons don't have any size ?

[Vince1963]

Thanks for the correction James.... and the "double slit thingy", But what as it to do with the "big bang"... or maybe the lack of it?. I'm confused

[Vince1963]

samandrew...i just can't get my head around the singularity and IF the universe was just energy, Then in what form was this energy?. Also the point i was making was there must be something smaller than a particle, because the universe fitted into something smaller than an atom, which in my logic must mean that the universe must have existed in some sort of different state before the so called big thingy.

[JamesF]

Thanks for the correction James.... and the "double slit thingy", But what as it to do with the "big bang"... or maybe the lack of it?. I'm confused

The double slit experiment is a perfect example of how macro-scale intuition doesn't apply at the level of particle physics. Very briefly, if you set up a solid barrier with two parallel slits in and fired ball-bearings at it, you'd expect a target behind to have two parallel lines of "hits" from the ball bearings that happened to pass throug the slits. If you do the same thing on a much smaller scale and this time fire electrons at two slits, that isn't what happens. You get an interference pattern across the entire target. At some point the electrons stop behaving like electrons and start behaving like waves originating from each slit and create the pattern on the target you'd expect to get with waves. So what happens if you just fire one electron at a time? You'd have to get two lines made by electrons as the pass through one of the slits one at a time because there's no electron going through the other slit to interfere with, right? Wrong. You still get an interference pattern. Unless (I think I have this right) you watch to see which slit the electron passes through. Do that and the electron only appears to pass through one slit and there's no interference. The electron appears to "know" whether you're watching or not and change its behaviour accordingly.

There is no way you would predict this behaviour from an understanding of macro-scale physics. It runs completely counter to our intuitive understanding of the way "normal" scale physics works.

For the same reason it is not logical to say that the quarks, bosons and leptons must be made up of smaller particles just because you can't see another way to compress them into a smaller space. They just don't behave in the way your intuition tells you they should if they were larger-scale, and in fact they sometimes behave in ways that just defy any explanation that might be possible in the larger-scale world.

When you step into the world of particle physics you have to leave all your preconceptions at the door. Different rules apply.

James

[DrRobin]

Hi,

The conventional theory is that the Universe started as a single point source and after an event (the big bang) it expanded rapidly (much less than a second) to fill the entire Universe. After this period of expansion, small amounts of matter clumped together due to very small differences in Gravity (which had only recently been invented) and these formed the early stars and eventually galaxies.

Now in the period of expansion most of the laws we understand today don't apply.

There was very little real matter;

Gravity didn't really exist or was a very weak force;

Time had no or very little meaning.

Basically we need a whole different set of rules, hence the search for the Higgs bosun and similar particles which are believed to have been dominate in the early stages of the period of expansion.

[JamesF]

This is half-remembered from a Jim Al-Khalili programme, but here's something else to think about:

It is believed to be possible for (some, perhaps?) elementary particles to just pop into existence from nowhere as long as their anti-particle counterpart is also created at the same time and as long as they annihilate each other before anyone notices. In fact, I think it's said that this actually happens all the time. If the conditions immediately after the big bang allowed it, perhaps it would have been possible for these particles to appear and then not disappear again. That way you wouldn't have to squash all matter down into a tiny point. It might "just appear" as space-time became "big enough" to hold it.

I'm way out of my depth with the physics at this point though. I'm not even sure I really understand what particle physicists mean by a "particle" beyond a convenient way to label "a set of features that appear to be related to each other". For example, I understand the particle physicists definition of a photon in terms of it's mass, spin, charge and so on, but those are just numbers. I have no idea what they really mean about the physical existence of a photon outside of the fact that it's a handy notion around which to hang a whole load of maths that works to describe the physical world. I don't have a problem with that, but labelling it as "a particle" may well serve to give the layman an impression that isn't strictly accurate.

James

[Auntystatic]

Hi Vince,

If I'm right your user name and cse's indicate you were born in that magical year of 1963..........

The year we had a great winter

Britain, US & USSR sign nuclear test ban treaty

Maarten Schmidt discovers enormous red shifts in quasars

US launches communications satellite Syncom 1

Explorer 17 attains Earth orbit (254/914 km)

Martin Luther King Jr's "I have a dream speech" at Lincoln Memorial

JFK proposes a joint US-Soviet voyage to the moon - well that never happened did it or we would have a moon base by now

I was born and as a celebration the BBC produce Doctor Who (p.s I wanna be in the 50th anniversary episode if any producers are reading)

I too left school with just cse's (grade 4 in math), like you I am constantly thinking about things, the double slit experiment has fascinated me for years, and what really gets my going is that even if you monitor it in a different building by tv camera, it still knows your watching it I really need to build me one!

The big bang got me thinking as it had to travel faster than the speed of light in the beginning, that was explained away to me by the inflation theory. Black holes get me too, all that matter squeezed in to a single point, just can not get my head around that yet. So your not alone with all these questions.

Many of these questions I have, have already been answered or have theories in progress, with me one question leads to another and I can not have a discussion if I haven't got the knowledge.

So earlier this year after reading through this forum, I decided to do something about it and later today my final application papers will be posted to the open university to start a degree in astrophysics, the maths scares the hell out of me, just because I don't understand it yet but at my age nothing should scare me except growing older and wrinkles and grey hair and.......well you get the point.

I love this place, you can get most of your questions answered by people with loads more knowledge than yourself, in a few years that might be me.

[JamesF]

So earlier this year after reading through this forum, I decided to do something about it and later today my final application papers will be posted to the open university to start a degree in astrophysics, the maths scares the hell out of me, just because I don't understand it yet but at my age nothing should scare me except growing older and wrinkles and grey hair and.......well you get the point.

Good on you Danielle. I hope it goes well. I am starting the certificate in astronomy thing at UCLAN this October too, all being well. I'd quite like to do something "bigger", but circumstances at the moment will not allow it.

James

[Folkert]

Nice stuff, the same reason I started to study Astronomy at the OU, to get beyond the pages in many popular science books that state: "we will not bother you with the math". And indeed, one thing I now understand is that a lot of this stuff cannot be understood, you just can derive it mathematically (I just had to solve a problem in which the temperature of the universe was requested for grand unification. The answer of 10²⁸ K cannot be understood beyond the plain characters (OK, it was very hot). I just accept that it cannot be understood. As Bohr said: "Those who claim to understand quantum theory clearly don't u derstand it"!

[Vince1963]

Hi Danielle... Your right in all you say, Great things happened in that year... (which changed the world). you seem to understand where i'm coming from. I need to know the answers and i need to understand the answers to everything, and something is just not logical to me. I too was thinking of OU. Taking the cosmology coarse, but unlike you i decided not to bother, simply because at pushing 50 what am i going to do with it?, its not as though it will improve my life in anyway.. I would love a job in astronomy, but that ship as sailed. so i'll just keep digging around on here.. There's a lot of "egg heads" on here LOL... no offence guy's. the thing is when i was a kid i wish i was the smart guy.But i chose the wrong path, School to me was just one big play ground and i regret it now.

Anyway... going back to my original post, I think its possible for scientists to find something smaller than a particle, that's assuming its not a wave..

I understand that normal physics don't apply in the beginning of creation and i understand that this is also something scientists say when they don't understand something.

After all there's still a lot of stuff that's not set in stone yet.....

As for the "big bang".. i don't think i'll ever get that one... I mean.. What was the catalyst? and who on earth can it expand from nothing to infinity? AND faster than light And in less than a Plank second (or something like that)... Well i must be the PLANK!... I seem to be on my own on this one.. well mostly.

THANKS FOR YOUR COMMENTS GUYS.... they do help me in my understanding of the great beautiful universe...

[JamesF]

Anyway... going back to my original post, I think its possible for scientists to find something smaller than a particle, that's assuming its not a wave..

Some things can be a particle or a wave depending on how you look at them. It's not really a question of being one or the other.

We know that some particles have zero rest mass, and that (some? My understanding of the physics is really being stretched here) elementary particles may have no dimension. What would it mean for something to be "smaller" than a particle that had no mass and/or no dimension? How could you tell?

String Theory is perhaps closest to what you're suggesting, but when I tried to get my head around String Theory my brain started to dribble out of my ears and I don't have that much to spare, so I stopped.

James

[George Jones]

and that (some? My understanding of the physics is really being stretched here) elementary particles may have no dimension.

What we can say is that, so far, there is no observational (experimental) evidence for:

1) a non-pointlike electron (i.e., for an electron that has non-zero size);

2) internal structure for electrons, quarks, and the Higgs.

More on 1). We can say that if an electron has size, then its size must be smaller than L metres, where L is an extremely small number. As we probe with higher and higher energies, we reduce the value of L. Some of the first results out of the LHC reduced the pre-LHC value of L for the electron.

More on 2). Again, as we probe with higher and higher energies we are more likely to "break apart" particles that have internal stucture (i.e., that are bound states of "smaller" particles).

String Theory is perhaps closest to what you're suggesting, but when I tried to get my head around String Theory my brain started to dribble out of my ears and I don't have that much to spare, so I stopped.

String theory is popular, but there are other models.

There are models, called techicolour, in which Higgs is a composite particle. There are other models in which electrons and quarks are made of particles called preons. The LHC is making it tough for these models.

[JamesF]

That's interesting George. Thank you.

James

[Cath]

Rather than say that the laws of physics are different now to what they were (or will be) ..

I myself would say that the laws of the universe (physics) are exactly the same now as they were (or will be) at ANY other time in the universes existence. It's not that the laws of physics change or are in any way different at other times or at other scales, it's just that OUR understanding of how the universe appears to work is so incomplete/incorrect.

I'd say it's our reasoning that is wrong/incomplete rather than the laws being different at atomic (and smaller) scales. Our knowledge of everything is still very new so we just haven't really got used to thinking differently about it all other than on our own scale/size in the universe (footballs, cars, hands, fingers etc).

Drop a tennis ball into a hopper and it will follow a certain path. Drop a tennis ball together with a thousand other tennis balls into a hopper at the same time and it will follow a different path based on it's interactions with all the other tennis balls. The ball doesn't follow different rules, it's just that it reacts differently according to it's current surroundings/conditions.

If you see what I'm trying to say/get at?

Don't you agree?

P.S. I've not long woke up and trying to put into words what's going through my mind on this little tablet is currently not easy

[Vince1963]

Rather than say that the laws of physics are different now to what they were (or will be) ..

I myself would say that the laws of the universe (physics) are exactly the same now as they were (or will be) at ANY other time in the universes existence. It's not that the laws of physics change or are in any way different at other times or at other scales, it's just that OUR understanding of how the universe appears to work is so incomplete/incorrect.

I'd say it's our reasoning that is wrong/incomplete rather than the laws being different at atomic (and smaller) scales. Our knowledge of everything is still very new so we just haven't really got used to thinking differently about it all other than on our own scale/size in the universe (footballs, cars, hands, fingers etc).

P.S. I've not long woke up and trying to put into words what's going through my mind on this little tablet is currently not easy

Hi Cath ... That's what i meant, I do understand that the laws of physics cannot change... Just our understanding of it, My wording could do with polishing up. I think i need to start thinking about what it is i'm writing before i put something down

[Cath]

It is believed to be possible for (some, perhaps?) elementary particles to just pop into existence from nowhere as long as their anti-particle counterpart is also created at the same time and as long as they annihilate each other before anyone notices.

Well, you see, their lies a problem for me - 'pop into existence from nowhere'.

When something like that is said by scientists what it really says to me is 'we have no idea where they came from, so lets just say they pop out of nowhere'.

What would make more sense to me would be if they were to say something like they condensed into our universe from the main source. The 'main source' being where the universe we appear to exist in may have leaked/expanded/escaped/overflowed from.

Note that the above ramblings are purely my own thoughts

[SamAndrew]

Well, you see, their lies a problem for me - 'pop into existence from nowhere'.

When something like that is said by scientists what it really says to me is 'we have no idea where they came from, so lets just say they pop out of nowhere'.

In this case the matter anti-matter pair popping into existence is a theory ? so it's not trying to explain an unusual observation.

I think of it like electrons and holes pairs within a semiconductor being generated by thermal energy, except in the case of matter/anti-matter, the energy comes from the vacuum energy of free space ?

[Ronnie67]

Quarks make up protons and neutrons, but, unlike protons and neutrons, quarks are not composed of any smaller particles. They are considered elementary particles.

Quarks could hypothetically be made up of preons, but this is inconclusive. So I suppose, quarks are made of strings.

However, if you actually wanted to know what less mass than a quark, but does not make up quarks, it would depend on the type, or flavour, of the quark. Up quarks have a mass of 2.4 MeV, down quarks have a mass of 4.8 MeV, charm quarks 1.27 MeV, strange quarks 104 MeV, top quarks 171.2 GeV, and bottom quarks 4.2 GeV.

[JulianO]

In this case the matter anti-matter pair popping into existence is a theory ? so it's not trying to explain an unusual observation.

It started as a theory, but there is now evidence to back it up, for instance http://en.wikipedia.org/wiki/Casimir_effect

I think of it like electrons and holes pairs within a semiconductor being generated by thermal energy, except in the case of matter/anti-matter, the energy comes from the vacuum energy of free space ?

It comes originally from Heisenbergs uncertainty principle. You can't say precisely what momentum and position a particle has.

This was extended to show that the same holds true for time/energy - and therefore you can be uncertain about the energy if the time is short enough. So energy is borrowed and paid back quickly. Maybe George will come by and fill in more of the details.

[DarkStar7]

All bosons such as the photon are much smaller than any Quark. The smallest fermion would have to have the highest energy because the Uncertainty Principles momentum part of the equation increases if we know more about the location. Obviously smaller particles require a higher degree of accuracy for its location. Therefore the Heaviest fermion is therefore the smallest.

[Anweniel]

Again, as we probe with higher and higher energies we are more likely to "break apart" particles that have internal stucture (i.e., that are bound states of "smaller" particles).

And therein lies another conundrum, by adding energy into making small 'entities' observable it makes them more difficult to observe/record as generally energetic 'entities' tend to be exciteable! I think it is likely there are smaller obejects than quarks but the issue is in proving (well really disproving) it. The real question for me is whether we can construct a sound enough model that we cannot disprove or is forever beyond our capabilities of measurement/observation. It all gets very complicated when you are talking small!

[DirkSteele]

There seems to be real misunderstanding of the word theory when used by scientists. “Theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment.” So quantum theory, general theory of relativity all stand up to repeated scrutiny of experiment and observation and provide predictions that can also be tested.

When most non-scientists state they have a theory, what they actually have is a hypothesis. “A hypothesis is an educated guess, based on observation. Usually, a hypothesis can be supported or refuted through experimentation or more observation.”

The idea of virtual particles is related to the idea of quantum fluctuations and is derived from the energy-time uncertainty principle. Virtual particles can be thought of as coming into existence as quantities, such as the electric field, which fluctuate around their expectation values as required by quantum mechanics. And further, the idea of virtual particles actually explains observations. The most well known is the Casimir Effect.

In quantum field theory, the Casimir effect is the physical forces arising from a quantized field. The well known example is of two uncharged metallic plates in a vacuum, placed a few micrometres apart, without any external electromagnetic field. In a non quantum (i.e classical) description, the lack of an external field also means that there is no field between the plates, and no force would be measured between them. When this field is instead studied using the QED vacuum (the lowest energy state of an electromagnetic field when the field is quantized) of quantum electrodynamics (the relativistic version of quantum field theory in electrodynamics), it is seen that the plates do affect the virtual photons which constitute the field, and generate a net force, which can either attract or repel the plates depending on how they are arranged.

Although the Casimir effect can be expressed in terms of virtual particles interacting with the objects, it is best described and more easily calculated in terms of the zero-point energy (To put my Sci-Fi geek hat on for a moment, those of you who have watched the Stargate TV show will have come across this – It is the power source the Ancients used) of a quantized field in the intervening space between the objects.

Zero-point energy is the lowest possible energy that a quantum mechanical physical system may have. Those of you who have some familiarity with quantum mechanics, will know this as the “ground state.” All quantum mechanical systems undergo fluctuations even in their ground state and have an associated zero-point energy. This is due to their wave-like nature. The uncertainty principle requires every physical system to have a zero-point energy greater than the minimum of its classical potential well, even at absolute zero. A great example of zero point energy is the case of liquid helium. Liquid helium does not freeze under atmospheric pressure at any temperature because of its zero-point energy.