Name: Seeing the Unseen: Demystifying Radiation from Rainbows to X-Rays | Abram Abdou | TEDxUF
Uploaded: 2026-03-19T12:19:58.000Z
Duration: 15 min 47 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

as a physicist, I like to say that I have two main jobs, the first one of which is to ask questions, and

the second one of which is to answer questions.

So thanks to all of you guys, I can say that I'm doing about one half of my job right now.

And while I do get asked questions that are often very intimate with what I study personally, I also get asked questions that are a bit more pragmatic.

And one such question that really stuck out to me is, can I actually see what you work on?

Now, this question makes a lot of sense to me because many physicists work with the theoretical, or at least that is the stigma.

And I've always been much more of a visual learner.

I dislike long, wordy explanations when I'd much rather be looking at something.

I'd much rather be looking at a figure, looking at a graph.

In fact, I think I speak for most of us in this room when I say that I'd much rather be looking at an image.

And what I want for all of you by the end of this talk is to understand how intimate radiation is with seeing.

I'm going to take a few moments to show you guys a collection of images.

And in these moments, I want you guys to think about what these images are and what they have in common.

Starting with this first image, the radioactive hazard safety symbol.

This is an image I'm sure many of you guys have seen in movies, maybe TV shows, or maybe real life.

This next image is a radiopharmaceutical.

And this one is used in positron emission tomography scans.

its more common name, PET scan, may ring a few more bells.

Now, what all these images have in common is that they all involve radiation in some form.

Yes, even the last one, when I tell people I work with radiation, a lot of times they can quite literally jump back.

And since it's my job to ask questions, I like to ask people, okay, what do you think of when I say the word radiation?

This could be because of the demographic I asked this question to, but I got some interesting results.

The first one of which was nuclear power plants, which, okay, makes perfect, complete sense to me.

And while both of these involve radiation in some form, radiation is actually a lot more common than just these two images.

You see an example of Radiation people tend to not think about are rainbows.

What you see when perceiving a rainbow is actually electromagnetic radiation.

Another example is the warmth we feel from a campfire.

We used to think that the fire would heat up the air and in turn the air would heat us up.

When in reality it was the warmth from that campfire, the radiation from that campfire that was making us feel warm the whole time.

And then there's also nuclear radiation, which while yes, you do get from your local power plants, you are more likely to get from trace amounts of radioactive potassium isotopes in our food supply.

Fun in the making and the production of this talk.

I found out that bananas were considered both a fruit and a berry.

This has nothing to do with the rest of this talk, but

what I will say is that while you can't choose if a nuclear power plant is built in your backyard, you can choose something else.

However, this talk is not about how to avoid radiation.

Nonionizing radiation were some of those examples I listed earlier.

The electromagnetic radiation from a rainbow, the warmth we feel from a campfire, and

interestingly enough, the radiation that music Travels on through AM&FM radio, if any of you guys listen to that.

Still, what I find particularly interesting is ionizing radiation.

It's a little bit different from some of those non ionizing examples from earlier.

And how it works is that a buildup of energy occurs.

And when that right amount of energy goes on and strikes the atom, an electron is removed from that atom.

To ionize just means to remove an electron.

An example of ionizing radiation that I think is very familiar to most of us in this room is the X ray.

We are going to segue out of physics and into history for a second.

And for the history lovers in your room, you have the time to shine.

For the science lovers, this may intrigue you as well as it intrigues me, because it is about the discovery and the creation of the first ever X ray.

And it all begins with this man right here.

It wouldn't be a TED talk if there wasn't a photo of a man way before my time right behind me.

And he was a physicist performing experiments on fluorescence utilizing vacuum tubes.

Now, this talk is also not about vacuum tubes, but

to give you some context, these were tubes that were mostly empty with a little bit of gas in them.

And what scientists found particularly intriguing about these tubes was that they would glow when you'd run electricity through them.

Now, Ronkin was one of those physicists studying this phenomenon, and

he'd cover these tubes when they weren't in use.

But then one day he noticed that despite the fact that the tubes were covered, a nearby screen across the room would glow.

And immediately he began to do some research and began to conclude that there was an invisible ray traveling from the tubes through the covering, all the way to the screen.

Now, it is not every day that the result of the unknown phenomenon you are studying is actually the result of an invisible ray.

And it's not every day where that conclusion would even be considered correct.

And because he didn't know what to name this ray, he decided to name it after.

In mathematics, it's commonly used to signify the unknown, the X ray.

Now, Ronkin knew this X ray could create images, and

he thought to himself that he wanted to create an image intentionally this time.

And his wife, Anna Ludwig, gave him her hand.

I show this image for two reasons, the first one of which was that it's the first ever X ray ever created.

But the second reason is that one of the first things ever captured through an X ray was.

Was not just skin, was not just bones, but

love, with Anna Ludwig's wedding ring being the most apparent feature of that image.

It's because that wedding ring absorbed more X rays than anything else in that photo, than the skin, than the bones.

And immediately scientists and physicians and clinicians began to see implications.

And they thought to themselves, if we can see differences between the skin and the bones, what other differences can we see?

Can we see differences in different kinds of bones?

Maybe we can see fractures, or just maybe we can use it to see things that we know shouldn't be there, in case any of you guys have kids that swallow things, or was a kid that swallowed things.

This was the first time ever and human history that we were ever able to see inside the body without cutting it open.

If every time I went to a hospital, I risked being put underneath the knife, I would be extremely hesitant to go to hospitals.