Category Archives: Chemistry

Should A Chair Fear Your Bottom? Well Actually, Science Says No.

Whilst sitting across from an empty seat, you can quickly begin to wonder who may sit opposite you. With a global population of around 7.6 billion people, it could be just anyone. The chances are that you may not know them or the story of their lives. But more than likely, they have a bum. And for a chair, their entire life is about waiting for the next one. But should a chair worry about being sat on? Physics tell us no.

Half And Half Again

You may be familiar with the old conundrum of infinite reduction. It goes something like this;

If you were to drop an object to the floor, it would cover half the total distance of the fall. Then half again, and again. If this continues, it will never reach the ground. So how is it that it can?

On paper, this makes total sense. But drop that paper, and it quickly becomes nonsense. Mathematics has a term for these rules that logically sound, but cannot be tested properly in our Universe, or don’t play out like they should in our day to day lives. These are called Axioms, and are designed to help us develop new tools to understand and change our world.

So for the chair, the foreign bum should never land, but it does. So perhaps the chair cannot find solace in Axioms. But actually, the bum will never truly touch it at all. That’s where physics comes in.

Bums and Bonds

Our universe is held together by four cardinal forces. There is gravity, the weak and strong nuclear forces and electromagnetism. Combined, they can be used to explain (to a high level of accuracy,) most of what we observe in our day to day lives, as well as in the distant past and far future. Their limits are found at the quantum level, but even now theoretical physicists are breaking those boundaries.

So what does this have to do with a Bum? Well a bum, mine, yours and Kim Kardashian’s, is made up of skin, fat, muscle and beneath that bone. These tissues are made of molecules, and those molecules, atoms. Those atoms are made of subatomic particles, such as quarks. No matter what, matter is what you are made of. And this matter must play by the rules.

At the atomic level, the strong nuclear force binds atoms together, gluing protons (which will repel each other,) together using substantial energy, (it is the breaking of these bonds that gives us nuclear fission, as opposed to their formation also utilising the weak force that fuels the stars.) The protons opposite number, the electron, also fiercely repels others. And its at this level that your bum atoms interact with those of the chair.

Very Small Distances

At this tiny level, the interactions between electrons are rather predictable. An electron is a curious thing, showing both the behaviour of a particle (like sand,) and a wave (like sound.) This is called wave/particle duality and plays a large role in how things interact. Even photons, the irreducible energy packets of light, share in these rules.

From a particle perspective, the electrons of two opposing atoms (and thus their larger molecules) cannot touch. They can get close, half by half, but never quite meet up. From a wave perspective, their ‘wave packets’ (i.e, the amplitudes of the signal in space-time) can overlap, but never fall in sequence. This means that the elections, and with them your bottom and a chair, can never quite touch.

So actually the old mathematical axiom runs true, but the explanation can be found in our universe as well as in the equation.

So Should Chairs Fear Bums?

From a perspective of touch, not really. But when it comes to smells, regardless of the physics, we still smell them. The interaction of a particle (of lets say, perfume,) and the cells in your nose still interact. You need a particle of something in your nose to smell it (and even then, it is your brain that creates the smell!) So although physics means that the chair can never  truly feel the bum rushing down upon it, it can smell it.

As can you.

What’s Next?

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  • Learn more about physics at physics.org
  • Let me know what you want to learn about.

The opinions expressed in this article are those of Dr Janaway alone and may not represent those of his affiliates. Remember, fear is natural, but how you choose to deal with it is a choice.  Image courtesy of Jes

 

 

 

 

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Are You Eating? Good! But Did You Know You Are Violating Cosmic Law?

First there was the Big Bang. Then, a few years later, there is the Big Mac. The future of our Universe is much like that of a Big Mac; to eventually decompose to nothingness. But you, at least for a while, can prevent that using the very energy a Big Mac delivers. How? Well within physics, the study of how matter works, you are actually opposing the Universe every time you take a bite.

Entropy and the End of the Universe

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A Broken Cup will never rebuild itself…

Imagine dropping a cup of tea (or coffee, whiskey, whatever you want.) First that cup will shatter, and its contents spread out to fill as much space as it can. This may just seem natural to you, but its actually a process. One of the laws of nature is that nature is lazy, and will often follow the path of least resistance. This is why water flows from high to low, and wind travels from high pressure to low pressure.

What happens is very simple. If a substance can drop to a lower energy state, it will. So to rebuild your tea cup you must use energy, kinetic energy from your hands, electrical energy in your brain and chemical energy in the glue. To refill it you must use electricity to boil water and kinetic energy to stir the tea and add sugar and milk. By re-dropping the broken cup you will never rebuild it.

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The Universe will eventually break down to almost nothing.

The universe has a tendency to disorder called Entropy. And that means over time all substances (be they huge planets or tiny atoms,) will eventually decompose into their constituent parts. This, theoretically, is one of the possible ends of the Universe. It is called ‘Heat Death‘, and will leave all we know as a dark, cold place. And it will happen to all of us (if we survive that long!)

How we Fight Entropy

Accepting that all structures will break down, how do we, a complex biological structure, prevent our own demise? Well, first we must understand something, pretty much everything in us is dead. We are formed of countless atoms, arranged in complex ways to perform different functions. Our looks, behaviours, lifespans and quirks are all based on evolution, which as acted on molecules for time immemorial.

The life bit is something quite special, and we still don’t know quite what it means. But all those dead bits need energy to become alive.

Biological structures need energy to work. Even as you read this you are using energy. Your heart is beating, your brain ‘thinking’ and your cells performing trillions of tiny operations to keep you alive. Its all wonderful, but needs energy to work. Without it, everything would fail, and break apart. When we die we follow the ultimate path of the Universe, to decompose and become molecules and eventually atoms ourselves.

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Kittens, like us, use energy to stay together.

Remember the Lion King, its a little like that, but without the Gazelles (for most of us!) By consuming energy we prevent our death, and in the terms of physics, entropy. We hold ourselves together at a molecular and biological level. By simply eating we defy the universe, and with it, keep ourselves alive.

So next time you have a cup of tea, remember that!

What Next?

  • Follow Ben on Twitter so you never miss an article
  • Tell me what you think in the comments or on Twitter
  • Read up on Entropy and the other possible ends of the Universe

The opinions above represent those of Dr Janaway alone and not necessarily those of his affiliates. I have relied heavily on the great work of Kurzgesagt, so give them a visit! If you have any ideas for articles, or would like to write with me, let me know on Twitter or drop me an email.

Images: 

Joanna Bourne

John Smith

Fuzzy Gerdes

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