how can radiation penetrate eveything but still leaves no visible holes
In: Physics
The short answer is that everything around us is already full of holes. The holes are frequently just too small to see or for most things to pass through, so we treat things like they are fully “solid” barriers even though they are not.
Many forms of radiation operate on a level where they are small enough to pass through these holes that most things can’t.
Do you mean radiation as in the form of the whole spectrum, i.e. microwaves, ultraviolet, infrared, x-rays, radio waves, etc?
Imagine the atoms that make up the stuff around us as trees seen from above, with the trunk being the nucleus and the interconnected leaves and branches being the electron clouds and bonds that hold the atoms together much like trees growing together in a forest.
Now if you tried to carry a whole bunch of already interlocked trees through this forest, you can appreciate that you’re going to have to cut down some of the trees in your way or else the branches are going to snag together. This is the same as a bullet or other big solid object blasting through a wall; their electron clouds really don’t like to overlap and like to resist this, so passing through the wall involves pushing all the intervening atoms out of the way, which creates a hole.
Very penetrating radiation particles are like small birds that can just fly between the branches; to them the branches might as well not be there, and so they can pass through the forest with relative ease without moving any atoms out of the way. I’d like to note that not all radiation particles are like this, some are large enough to act like individual trees, and these do often interact with the “forest” of atoms much more. That being said, they still have much less mass than say a bullet, so they’re not going to be moving many atoms aside. However, they CAN move aside single atoms very efficiently, which can be a very bad thing when those atoms are parts of your DNA. That’s why radiation can be so good at screwing up your DNA and giving you cancer.
The holes are already there, they’re just too small for you normally
Objects are uniform solid things, most of the volume is just empty space between the atoms, but because its electrons and your electrons push back at each other from a distance it seems solid to you
Objects are more like a dense forest. If you try to drive a big car through it you’ll just get stuck because there isn’t enough space between the trees, but you can walk through it and if you were the size of a mouse then there’d be tons of room between the trees to sneak through
Radiation is little high energy particles like electrons or photons like gamma rays that are soooo tiny that they can easily squeeze through the space between the cores of atoms and get out the other side. If you want to stop them then you need to put enough big atoms packed closely together in its path (like in a dense element like lead) so that the particle will almost certainly hit something before it can pop out the other side. Even when it does hit something it generally just gets absorbed and turned into a bit of heat in the material rather than blowing a hole through it like a bullet might
Imagine a volleyball net. There are three main types of radiation: alpha, which would be a volleyball. Then beta, which would be a tennis ball. And gamma, which would be a grain of salt (but not really since it is an electromagnetic wave). Scaling only for an example.
Now throw these at the net and see what happens. The net is the matter around us. It can block some radiation, but not all.
Edit: can’t believe I am getting this recognition for such a simple explanation, thank you!
It’s important to note that *not all* radiation can penetrate everything. Alpha radiation can only travel a few feet and is stopped by paper. Radio waves are oftentimes blocked/scrambled by metallic frames.
Otherwise, it’s similar to how a pebble can get dropped in a pool of water and sink to the bottom without leaving any holes. It has enough mass and energy to push through the water. In the case of radioactive particles traveling “through matter”, it’s really traveling through the gaps and space in the individual atoms and molecules that make up the objects you see.
The same way that light passes through glass.
Some radiation is good at getting through different things, and/or some things are transparent to different kinds of radiation.
For example, the normal frequency for Wifi (2.4ghz), is pretty good at getting through most things. It gets blocked by metal and water, mostly. If you imagine a strong light bulb sitting where your router is, and that everything in your home that isn’t water and metal were glass, you would have a pretty good idea of where your wifi works well. Wherever a shadow is cast, it will not have the strongest signal.
To very powerful radiation, everything is glass.
You know how light goes through glass, water and other transparent things?
Light is a type of radiation. And if you could see radiation, things that it passed through would look transparent.
Related mind blowing fact: neutrinos can travel through solid lead that’s one light year thick without hitting anything.
Here’s one super abstract when you think about it.
Particles are super duper tiny, and they don’t really touch anything in a physical way.
What they do have are super strong force field surrounding them (think like the magnetic field around a magnet), and these force fields are how they actually interact with stuff.
So now imagine one of those videos online where a person gets inside of a giant clear plastic ball (sort of like a hamster ball) and rolls down a hill.
They never really “touch” anything, but the ball does, and the ball travels with them, so they can effectively “interact” with stuff.
And you could also “interact” with them using the ball.
So imagine now that you are waiting for them at the bottom of the hill, and let’s also imagine that you’re 50 ft tall.
And when the human hamster ball with a person inside comes up to you, you run up to it and give it a field goal style soccer kick, and the ball and the little person inside sail off into the sunset never to return.
But you never really touched the person, you just kicked the plastic ball and the little person sailed along for the ride.
Now let’s imagine that we replace the person in the hamster ball with a super powerful magnet.
Let’s now also imagine that we now make the sloping track out of metal, and we replace your foot with metal as well.
With his new arrangement, the exact same thing would happen.
The super powerful magnet wood float above the ground without ever touching it, and sail down the hill towards your foot
And if you did a slow motion video capture when you went in for the kick, you would see that your foot approached to the magnet, but the magnet began flying away from your foot without the two of them ever actually touching.
But magnets can repel as well as attack. And particles are like “complex” magnets because they can have multiple different “kinds” of force fields up at the same time.
So they literally can be attracting another particle with one of their force fields, and pushing it away with another force at the same.
Think,
“Oh God I need you near me!!! No wait… not that close…”
So the particles form like a net, or a lattice (think like those old school 1970s bead curtains, but without the string).
So each particle clings on to all of its neighbors super duper hard, BUT pushes them away even harder if they get too close.
So what you see as a physical wall, is really a cloud of particles made up almost completely of empty space, with the super tiny particles clinging on for dear life to their extremely distant next door neighbors, but always maintaining a tremendous distance from anyone else at the same time.
So NOW when you swing your metal booted foot (from way back up top when you kicked that magnet) at the wall, usually one of two things happens.
1. The “attractive” forces between the next door neighbors particles in the wall holds up, and your boot bounced off (think ping pong ball vs a wall).
2. OR you kick hard enough and your boot physically breaks those bonds of attraction and soves it ways past the particles (think NFL linebacker) and leaves a hole.
AND radiation is the same way.
Remember that radiation is just the name that we give for the electromagnetic field as it moves through space. EM radiation is made up of photons and includes visible light, UV, infrared, X-Rays, cosmic rays, gamma rays, radio waves, etc.
So when radiation hits a wall, it might.
1. Bounce off like a ping pong ball. This is actually how you “see” things.
Visible light has a pretty low energy, and it can’t really penetrate through most things
So the reason why any object at all looks solid to you, instead of looking like what it really is (which is an almost completely empty cloud of particles), it’s because that visible light when trying to move through that wall, tries to violate the personal space and get too close to those particles, and their repulsory force field kicks the light right back out at you towards your eyeballs, and that’s what you see.
SO what happens when EM radiation penetrates the wall? Why doesn’t it leave holes like when you kick a hole in the wall?
The answer is because light is made up of photons which are extremely extremely tiny.
So when they don’t have enough energy to push through the repulsor field of the particles that make up the wall, they just bounce back towards you.
But when they DO have enough energy to pass through the repulsor fields on those particles, there’s so much empty space for the photons to move around in, they can pass clean from one side of the wall to the other without ever actually touching anything or having to move anything out of the way (unlike your boot, which actually had to move particles out of the way in order to get through)
That isn’t to say the radiation doesn’t have any effect at all on the things that passes through.
Quite the opposite.
High energy radiation positively shred the things that passes through.
But because each individual photon is so tiny, all that damage is only going to be on that super tiny particle level.
So if you get hit in the chest with a lethal blast of radiation, it’s not going to put a hole in you.
In fact you probably wouldn’t even be able to feel it.
Because all those photons were doing on the way through your body was just moving one particle a little bit this way, another particle a little bit that way, nothing you’d even be able to feel.
But on your most fragile bits (like the DNA inside your cells) this can cause irreversible damage.
Please let me know if this helps and if you have any additional questions at all!
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