Something has always struck me as counter-intuitive: when reading about high-energy experiments such as the LHC, they are always looking for stuff on a really small scale with MASSIVE energies.
I guess this quote illustrates it (Wikipedia: Gravitons):
Attempts to extend the Standard Model or other quantum field theories by adding gravitons run into serious theoretical difficulties at high energies…
Shouldn't something really small in size be really low in energy?
Take the Higgs boson for instance. I just can't grasp it. If this particle is mediating a fundamental interaction that isn't very strong, how come it isn't much easier to see? Wouldn't we be swimming in a soup of them?
Finally, with gravitons (Wikipedia: Gravitons again):
For example, a detector with the mass of Jupiter and 100% efficiency, placed in close orbit around a neutron star, would only be expected to observe one graviton every 10 years, even under the most favorable conditions.
But, I mean, doesn't gravity exist everywhere?
I run into this apparent paradox in regard to all kinds of particles, when reading about physics. I'm sure it's just some fundamental point I'm not getting.
Best Answer
In high energy physics the energy scale is very important. As you said matter is probed at smaller and smaller distances, and that requires more energy. Why is that?
Well in natural units ($c = \hbar = 1$) we have some quantities that mix with each other, i.e there is very little difference between them (mainly just a proportionality constant) In particular:
$$ [Velocity] = number$$ $$ [Energy] = [Mass] = [Momentum] $$ and $$ [Mass] = [Length]^{-1} $$
From this it follows that $[Energy]$ is actually just inverse $[Length]$ hence the smaller the distances probed, the higher the energy scales.
If these above relations seem strange think of them like this. The highest achievable velocity is the speed of light $c$ and we already set that to one by our choice of natural units. This means that any other velocity will range from $0 \leq v \leq 1$ thus its a scalar.
Also, from $E^2 = (pc)^2 + (mc^2)^2$ it follows that $E^2 = p^2 + m^2$. The last one, which is the core of your question follows from the fact that $\hbar/(mc)$ has units of length and in natural units it becomes $m^{-1}$.
To finish up, your last point about gravity follows from the fact that gravitons interact very weakly at the energy scales we are probing because gravity only becomes relevant at extremely small distances of the order of the Planck Length,
$$\ell _{{\text{P}}}={\sqrt {\frac {\hbar G}{c^{3}}}}\approx 1.616\;199(97)\times 10^{{-35}}{\mbox{ m}}$$
This equates to huge energies that we have no access to currently. All this done above is called dimensional analysis.
Edit: To address the Higgs boson part of the answer:
Don't consider the Higgs boson as a fundamental interaction because it is not. The reason we need high energies to produce the Higgs is for a different reason. As others pointed out, the Higgs is an excitation of the Higgs field. The boson itself is very massive. Remember mass = energy. To produce a massive boson you need to supply at least enough energy to produce its mass. This kind of energy is not available in our everyday lives. Only the LHC has enough power to produce energy scales that high. But that doesn't affect other particles interacting with the Higgs field to gain mass.
Edit: Added small talk on gravity to address the OP's question in the comments:
For a subatomic particle, the gravitational effects are extremely small due to their tiny masses. For gravity to become relevant for individual particles we need to investigate them at the planck length scales. But gravity in general is relevant in the universe, and that is because astronomical objects are very massive and their combined mass produces gravitational fields that have observable effects.