Laura Nassar makes us question all we thought we knew about the world around us
by Laura Nassar
No matter how smart we think we are, there is always a concept out there ready to laugh in the face of our logic. We sit back, smug with knowledge, chuckling as Hermione attends two classes at once. Yet the unsettling truth is that the child who believes in these stories is unwittingly closer to the reality of the universe than we are.
Starting with primary school, we are conditioned to order our thoughts in neat progressions. Everything has a cause and effect, time moves linearly, and the world functions according to understandable, predictable rules.
What if I told you this was all nonsense?
Don’t worry, this isn’t some big philosophical revelation, just quantum physics throwing a brick at our entire belief system. Following the laws of the quantum world:
Hamlet can’t ponder whether “to be” or “not to be” because he is simultaneously dead and alive
Physicists refer to this concept as “quantum superposition”. A famous example you may already be aware of is Schrödinger’s cat (but let’s keep the Hamlet analogy because it’s more fun). Let’s put Hamlet in a box. You would think he is either dead or alive in that box. The weird thing is, Hamlet is BOTH dead and alive, up until you open the box, which is when he obtains a definitive state. This is not due to our uncertainty. In other words, we are not assuming that he is both dead and alive simply because we don’t know the answer. In the quantum world there actually is no answer. He is literally dead and alive at the same time until we observe him.
Ballerinas are having a collective meltdown because spinning clockwise in Cambridge means you can only spin counter-clockwise in New York
The ballerinas are victims of “quantum entanglement”. Two quantum ballerinas called Sara and Maya have been best friends for years. They both studied at Cambridge, but now live at opposite ends of the world. The weird thing is, if Sara pirouettes clockwise in Cambridge, Maya instantly whirls counter-clockwise in New York! This is not a telepathic connection, but what physicists call quantum entanglement.
“Einstein referred to this phenomenon as “spooky action at a distance”.”
But here’s an even dizzier thought; Sara and Maya seem to be spinning both ways at once (much like how Hamlet was both dead and alive at once). It is only when an outsider observes Sara dancing, that she “chooses” a specific spin direction. Let’s say Sara chose clockwise. At that exact moment, Maya will find herself spinning counter-clockwise regardless of how far away she is from Sara. This seemingly telepathic connection can occur between entangled quantum particles at apparently infinite distances. Einstein referred to this phenomenon as “spooky action at a distance”.
Catapulted stones from the Trojan War suddenly transform into a tsunami
This refers to arguably the most famous concept in quantum physics known as wave-particle duality. Greek catapults launch stones at Troy’s walls, stones that are about to make Houdini proud. One second they’re determined projectiles but the next they morph into a fluid collective wave; a tsunami crashing over the defences. (Until they are observed, then they suddenly transform back into stones, of course).
But stones lack the panache for such quantum shenanigans. This is reserved for electrons (pfft, show-offs). Quantum particles like electrons have been shown to act as both waves and particles, and this is the property responsible for the remarkable resolution we see in electron microscopes today!
Newton is over at the Physics department, distraught, because his apple has rudely vanished into the floor
The audacity! Poor Isaac, left to grapple with the insolence of a fruit that dared to defy the very law he established. Well, that’s just how it works in the quantum world; barriers are merely suggestions. We commoners would call this teleportation, but physicists know that this is a very real phenomenon called “quantum tunnelling”. It’s a bit like losing your car, and finding it parked on your roof. It doesn’t make sense. Luckily quantum particles couldn’t care less about our logic, they’re just doing their thing.
“It seems the only certainty is the uncertainty of it all.”
The secret is related to their wave-particle duality. Think of how sound can travel through a wall because of its nature as a wave. It’s kind of like that, but not quite. Trust me, delving deeper would only further muddy the waters.
So, in the quantum world, where apples do as they please and particles purposefully confuse us, it seems the only certainty is the uncertainty of it all.
So why does this weird stuff not occur at a macroscopic scale?
Why don’t we see ballerinas spinning clockwise and counter-clockwise simultaneously? How come Hamlet can either be or not be? How come you can’t just teleport to the other side of the door in the middle of an awful date
The answer all lies in observation.
In all previous examples, when a quantum particle was “observed” it was forced to choose one particular state. Clockwise or counter-clockwise, particle or wave… But only when it was being observed.
At a macro scale, everything is being observed all the time!
Beyond Schrödinger’s cat: Quantum effects in biology
Of course, not observation in the literal sense. For example:
A speck of dust hits a wall due to random motion. Although nobody witnessed this collision, the wall’s texture, the initial speed and spin of the speck, and the angle of impact all influence how the collision unfolds. The collision itself is an act of observation! The collision compels the speck and the wall to assume specific states.
Our macroscopic world is teeming with trillions of particles and objects constantly interacting, which means that observation is an ever-present phenomenon. Due to constant observation, there is no chance of any quantum weirdness arising at our scale.
In the quantum world, a particle such as an electron is surrounded by vast nothingness. So much emptiness relatively surrounds the electron, to an extent our brains cannot even comprehend. There is very little chance that it could be accidentally “observed”, which is why quantum weirdness can exist in the world of the tiny.
Heat transfer might behave differently in transparent objects.
DR. ALFREDO CARPINETI
Senior Staff Writer & Space Correspondent
Edited by Maddy Chapman
Transparent and translucent materials might transfer heat differently from other solids.
Image Credit: Cg_loser/shutterstock.com
Heat transfer is among the oldest known laws of physics. First formalized by Netwon and then generalized by Jean-Baptiste Joseph Fourier, the eponymous Fourier’s Law has been unrivaled for centuries to explain how heat diffuses through a solid object. However, researchers have now discovered that the laws are definitely not complete.
It had been established that at the nanoscale Fourier’s law doesn’t explain all the transfer of heat. But still, the law could be seen as a generalization that works on the macroscale. Yet researchers were curious to see if those exceptions could also happen in something big – and it turns out they do under the right conditions.
“This research began with a simple question,” Steve Granick, Robert K. Barrett Professor of Polymer Science and Engineering at the University of Massachusetts Amherst and the paper’s senior author, said in a statement. “What if heat could be transmitted by another pathway, not just the one that people had assumed?”
Their simple idea was that heat can transfer through conduction in a solid but if that solid was transparent it could also transfer by radiation. They tested this in translucent polymers and inorganic glasses.
They placed these materials in a vacuum so air transfer didn’t play a role, and they heated up one side of these materials with a laser and measured with thermal cameras the diffusion of heat. Fourier’s Law alone could not explain what the team was able to observe.
“No one has tried this before,” added lead author Kaikai Zheng also from UMass Amherst. “There’s something unexpected happening within translucent polymers.”
“It’s not that Fourier’s Law is wrong,” Granick was quick to stress, “just that it doesn’t explain everything we see when it comes to heat transmission. Fundamental research like ours gives us an expanded understanding of how heat works, which will offer engineers new strategies for designing heat circuits.”
The team believes that the translucent materials allow for energy to radiate internally. And this radiation heats up imperfections in the material which become secondary heat sources that also radiate through the material. This is why opaque materials do not show such a deviation from Fourier’s law.
The paper is published in the Proceedings of the National Academy of Sciences.
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