from the world's big
Are birds using quantum entanglement to navigate?
Sounds wild, but it may well be so.
- Birds' navigation using Earth's very faint magnetic fields suggests an incredible level of sensitivity.
- There's reason to think that sensitivity may be based on quantum entanglement in cryptochrome in their eyes.
- Identifying the role of quantum physics in biology could lead, well, who knows where?
Okay, this is far from confirmed, but it's pretty radical, and exciting. It's a possible and plausible answer to a question that's puzzled biologists ever since the manner in which birds navigate became apparent. The question is: How can birds possibly be able to perceive and follow something as faint as the Earth's magnetic field? The possible answer? It may be that they perceive it through the interaction of entangled quantum particles in their eyes.
Behind this hypothesis is years of confirming and seeking to explain birds' phenomenal sensitivity to Earth's magnetic field. The most plausible explanation for it has to do with the effect of the magnetic field on entangled molecules of a chemical in birds' eyes, Cry4, or cryptochrome. Other animals, and plants, share the chemical, though it's believed that birds have developed their own variant. Quantum entanglement, Einstein's "spooky action at a distance," is a topic that comes up often at Big Think because it's a theoretical vehicle upon which some of the strangest and most interesting new ideas ride. Here's what we mean:
- The bizarre and wonderful world of quantum theory—and how understanding it has ultimately changed our lives
- Why a 'genius' scientist thinks our consciousness originates at the quantum level
- The universe may be conscious, say prominent scientists
And now this.
When a photon, a light particle, hits a cryptochrome molecule in a bird's eye, it knocks loose an electron that may then become associated with a second molecule. The two molecules then both have an odd number of electrons, and they become a radical pair. Since the oddness of both of these radicals was created simultaneously by that loosened electron, the spins of one electron in each molecule of cryptochrome become locked together in relation to each other and the radical pair becomes entangled.
This entangled state is extremely fragile, and temporary, so it won't survive beyond just 100 microseconds (1/10,000th of a second). But during that brief interim, the radical pair will be in either one of two states. The suspicion is that the Earth's magnetic field affects the amount of time the molecules spend in either state, and changes to the duration of these states somehow tells the bird where he or she is. The exact means by which the bird perceives them is unknown, though it's been suggested that it may have to do with one or both states causing the presence of absence of some as-yet-unidentifed chemical.
Why this isn’t just craziness
Supercomputer model of Earth's magnetic field.
This might not seem to make sense because magnetic fields are so weak, but it's real. How weak? "The energy of interaction of a molecule with a ≈50-μT magnetic field is >6 orders of magnitude smaller than the average thermal energy kBT, which in turn is 10–100 times smaller than the strength of a chemical bond," according to a 2009 study, Chemical magnetoreception in birds: The radical pair mechanism. However, "It has been known since the 1970s that certain chemical reactions do in fact respond to applied magnetic fields." (Our emphasis.) The study also notes that radicals always seem to be involved.
The radical pair theory is really the best explanation for birds' navigation systems we have, since experiments attempting to detect effects of magnetic fields directly on biological processes — bypassing chemistry — have come up empty-handed.
The study proposes that perhaps photons are throwing electrons far enough from their normal thermal equilibrium that they remain entangled long enough to respond to the subtle cues coming from the planet's magnetic field. Quantum entangled particles created by scientists last for mere nanoseconds. One such scientist, Erik Gauger, tells Nova, "It seems nature has found a way to make these quantum states live much longer than we'd expect, and much longer than we can do in the lab. No one thought that was possible."
Proof of birds' sensitivity
Map of Earth's magnetic field, 1895.
A number of experiments to confirm what's going on are cited in the paper, some of which the authors find more convincing than others. However, the most compelling evidence of birds' amazing sensitivity comes from experiments with caged European robins, whose navigation abilities were easily disrupted. "Linearly polarized radio frequency fields 100 times weaker than the Earth's field (≈500 nT), with frequencies of 7.0 MHz or 1.315 MHz, are sufficient to disrupt the migratory orientation of caged European robins." (Again our emphasis.) Playing with the magnetic field also easily baffled the birds, with researchers finding a "20–30% increase or decrease in the intensity of the ambient magnetic field is sufficient to disorient caged birds."
Clearly, avians possess an almost unbelievably delicate sensing mechanism of some sort. The intersection of quantum mechanics and biology — even human biology — is a fascinating notion. As mentioned above, some wonder if it may also relate to consciousness and other currently bewildering phenomena. If we can come to fully understand the mechanics or chemistry of birds' impressive capabilities, what other mysteries might we be able to unlock?
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Join multiple Tony and Emmy Award-winning actress Judith Light live on Big Think at 2 pm ET on Monday.
From "if-by-whiskey" to the McNamara fallacy, being able to spot logical missteps is an invaluable skill.
- A fallacy is the use of invalid or faulty reasoning in an argument.
- There are two broad types of logical fallacies: formal and informal.
- A formal fallacy describes a flaw in the construction of a deductive argument, while an informal fallacy describes an error in reasoning.
Appeal to privacy<p>When someone behaves in a way that negatively affects (or could affect) others, but then gets upset when others criticize their behavior, they're likely engaging in the appeal to privacy — or "mind your own business" — fallacy. Examples:<br></p><ul><li>Someone who speeds excessively on the highway, considering his driving to be his own business.</li><li>Someone who doesn't see a reason to bathe or wear deodorant, but then boards a packed 10-hour flight.</li></ul><p>Language to watch out for: "You're not the boss of me." "Worry about yourself."</p>
Sunk cost fallacy<p>When someone argues for continuing a course of action despite evidence showing it's a mistake, it's often a sunk cost fallacy. The flawed logic here is something like: "We've already invested so much in this plan, we can't give up now." Examples:<br></p><ul><li>Someone who intentionally overeats at an all-you-can-eat buffet just to get their "money's worth"</li><li>A scientist who won't admit his theory is incorrect because it would be too painful or costly</li></ul><p>Language to watch out for: "We must stay the course." "I've already invested so much...." "We've always done it this way, so we'll keep doing it this way."</p>
If-by-whiskey<p>This fallacy is named after a speech given in 1952 by <a href="https://en.wikipedia.org/wiki/Noah_S._Sweat" target="_blank">Noah S. "Soggy" Sweat, Jr.</a>, a state representative for <a href="https://en.wikipedia.org/wiki/Mississippi" target="_blank">Mississippi</a>, on the subject of whether the state should legalize alcohol. Sweat's argument on prohibition was (to paraphrase):<br></p><p><em>If, by whiskey, you mean the devil's brew that causes so many problems in society, then I'm against it. But if whiskey means the oil of conversation, the philosopher's wine, "</em><em>the stimulating drink that puts the spring in the old gentleman's step on a frosty, crispy morning;" then I am certainly for it.</em></p>
Slippery slope<p>This fallacy involves arguing against a position because you think choosing it would start a chain reaction of bad things, even though there's little evidence to support your claim. Example:<br></p><ul><li>"We can't allow abortion because then society will lose its general respect for life, and it'll become harder to punish people for committing violent acts like murder."</li><li>"We can't legalize gay marriage. If we do, what's next? Allowing people to marry cats and dogs?" (Some people actually made this <a href="https://www.daytondailynews.com/news/national/cats-marrying-dogs-and-five-other-things-same-sex-marriage-won-mean/dLV9jKqkJOWUFZrSBETWkK/" target="_blank">argument</a> before same-sex marriage was legalized in the U.S.)</li></ul><p>Of course, sometimes decisions <em>do </em>start a chain reaction, which could be bad. The slippery slope device only becomes a fallacy when there's no evidence to suggest that chain reaction would actually occur.</p><p>Language to watch out for: "If we do that, then what's next?"</p>
"There is no alternative"<p><span style="background-color: initial;">A modification of the </span><a href="https://en.wikipedia.org/wiki/False_dilemma" target="_blank" style="background-color: initial;">false dilemma</a><span style="background-color: initial;">, this fallacy (often abbreviated to TINA) argues for a specific position because there are no realistic alternatives. Former British Prime Minister Margaret Thatcher used this exact line as a slogan to defend capitalism, and it's still used today to that same end: Sure, capitalism has its problems, but we've seen the horrors that occur when we try anything else, so there is no alternative.</span><br></p><p>Language to watch out for: "If I had a magic wand…" "What <em>else</em> are we going to do?!"</p>
Ad hoc arguments<p>An ad hoc argument isn't really a logical fallacy, but it is a fallacious rhetorical strategy that's common and often hard to spot. It occurs when someone's claim is threatened with counterevidence, so they come up with a rationale to dismiss the counterevidence, hoping to protect their original claim. Ad hoc claims aren't designed to be generalizable. Instead, they're typically invented in the moment. <a href="https://rationalwiki.org/wiki/Ad_hoc" target="_blank">RationalWiki</a> provides an example:<br></p><p style="margin-left: 20px;">Alice: "It is clearly said in the Bible that the Ark was 450 feet long, 75 feet wide and 45 feet high."</p><p style="margin-left: 20px;">Bob: "A purely wooden vessel of that size could not be constructed; the largest real wooden vessels were Chinese treasure ships which required iron hoops to build their keels. Even the <em>Wyoming</em> which was built in 1909 and had iron braces had problems with her hull flexing and opening up and needed constant mechanical pumping to stop her hold flooding."</p><p style="margin-left: 20px;">Alice: "It's possible that God intervened and allowed the Ark to float, and since we don't know what gopher wood is, it is possible that it is a much stronger form of wood than any that comes from a modern tree."</p>
Snow job<p><span style="background-color: initial;">This fallacy occurs when someone doesn't really have a strong argument, so they just throw a bunch of irrelevant facts, numbers, anecdotes and other information at the audience to confuse the issue, making it harder to refute the original claim. Example:</span><br></p><ul><li>A tobacco company spokesperson who is confronted about the health risks of smoking, but then proceeds to show graph after graph depicting many of the other ways people develop cancer, and how cancer metastasizes in the body, etc.</li></ul><p>Watch out for long-winded, data-heavy arguments that seem confusing by design.</p>
McNamara fallacy<p>Named after <a href="https://en.wikipedia.org/wiki/Robert_McNamara" target="_blank">Robert McNamara</a>, the <a href="https://en.wikipedia.org/wiki/United_States_Secretary_of_Defense" target="_blank">U.S. secretary of defense</a> from 1961 to 1968, this fallacy occurs when decisions are made based solely on <em>quantitative metrics or observations,</em> ignoring other factors. It stems from the Vietnam War, in which McNamara sought to develop a formula to measure progress in the war. He decided on bodycount. But this "objective" formula didn't account for other important factors, such as the possibility that the Vietnamese people would never surrender.<br></p><p>You could also imagine this fallacy playing out in a medical situation. Imagine a terminal cancer patient has a tumor, and a certain procedure helps to reduce the size of the tumor, but also causes a lot of pain. Ignoring quality of life would be an example of the McNamara fallacy.</p><p>Language to watch out for: "You can't measure that, so it's not important."</p>
A new study looks at what would happen to human language on a long journey to other star systems.
- A new study proposes that language could change dramatically on long space voyages.
- Spacefaring people might lose the ability to understand the people of Earth.
- This scenario is of particular concern for potential "generation ships".
Generation Ships<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="a1e6445c7168d293a6da3f9600f534a2"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/H2f0Wd3zNj0?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Many of the most popular apps are about self-improvement.
Emotions are the newest hot commodity, and we can't get enough.