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8 Shocking Things We Learned From Stephen Hawking's Book From the idea that our universe is one among many, to the revelation that mathematician Pythagoras didn't actually invent the Pythagorean theorem, here are eight shocking things we learned from reading physicist Stephen Hawking's new book, "The Grand Design," written with fellow physicist Leonard Mlodinow of Caltech. The book, covering major questions about the nature and origin of the universe, was released Sept. 7 by its publisher, Bantam. The past is possibility According to Hawking and Mlodinow, one consequence of the theory of quantum mechanics is that events in the past that were not directly observed did not happen in a definite way. Instead they happened in all possible ways. This is related to the probabilistic nature of matter and energy revealed by quantum mechanics: Unless forced to choose a particular state by direct interference from an outside observation, things will hover in a state of uncertainty. For example, if all we know is that a particle traveled from point A to point B, then it is not true that the particle took a definite path and we just don't know what it is. Rather, that particle simultaneously took every possible path connecting the two points. Yeah, we're still trying to wrap our brains around this. The authors sum up: "No matter how thorough our observation of the present, the (unobserved) past, like the future, is indefinite and exists only as a spectrum of possibilities." The power of light This fun fact: A 1-watt night-light emits a billion billion photons each second. Photons are the little packets that light comes in. Confusingly, they, like all particles, behave as both a particle and a wave. Theory of everything If there is any "theory of everything" that can describe the whole universe, it is M theory, according to Hawking and Mlodinow. This model is a version of string theory, which posits that at the tiniest levels all particles are fundamentally little loops of string that vibrate at different frequencies. And, if true, all matter and energy would follow rules derived from the nature of these strings. "M theory is the only model that has all the properties we think the final theory ought to have," the authors write. One consequence of this theory is that our universe is not the only one – untold numbers of cousin universes exist with different physical laws and properties. General relativity If most people think of general relativity at all, they assume this high-minded idea of Einstein's applies only to super-large objects completely outside the realm of normal life, such as galaxies and black holes. But actually, the warping of space-time does affect things we know and use, the authors point out. "If general relativity were not taken into account in GPS satellite navigation systems, errors in global positions would accumulate at a rate of about ten kilometers each day," the book states. That's because general relativity describes how time flows slower the closer an object is to a large mass. Thus, depending on satellites' distances from Earth, their onboard clocks will run at slightly different speeds, which could offset position calculations unless this effect is taken into account." Oppressed fish A few years ago, the city council of Monza, Italy, barred pet owners from keeping goldfish in curved bowls. This law was meant to protect the poor fish from a distorted nature of reality, since bent light might show them an odd portrayal of their surroundings. Hawking and Mlodinow bring up the incident to make the point that it is impossible to know the true nature of reality. We think we have an accurate picture of what's going on, but how would we know if we were metaphorically living in a giant fishbowl of our own, since we would never be able to see outside our own point of view to compare? Pythagoras stole the credit In passing, the authors casually assert that the famous Greek mathematician Pythagoras did not actually discover the Pythagorean theorem. A little digging suggests the formula (a2 + b2 = c2, which describes the relationship between the three sides of a right triangle) was actually known earlier. The Babylonians, for example, seem to have documented the basic idea in ancient mathematical tablets before Pythagoras came on the scene in 570 B.C. Quarks are never lonely Quarks, the adorably named building blocks of protons and neutrons, come only in groups, never alone. Apparently, the force that binds quarks together increases with distance, so the farther one tries to pry a lone quark away, the harder it will pull back. Therefore, free quarks never exist in nature. Protons and neutrons are both made of three quarks. (Protons contain two "up"-flavored quarks and one "down," while neutrons have two downs and one up.) The universe is its own creator One of the most talked-about assertions in the whole book is that we don't need the idea of God to explain what sparked the creation of the universe. "It is not necessary to invoke God to light the blue touch paper and set the universe going," Hawking and Mlodinow write. Instead, the laws of science alone can explain why the universe began. Our modern understanding of time suggests that it is just another dimension, like space. Thus it doesn't have a beginning. "Because there is a law such as gravity, the universe can and will create itself from nothing," they write. "Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist."
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Što nam donosi znanost 21. stoljeća? Od ideje da je naš svemir samo jedan od mnogih, pa do lažne stvarnosti... Pogledajte kojih 5 neobičnih stvari smo naučili iz Hawkingove knjige "The Grand Design", koju je napisao u suradnji s fizičarem Leonardom Mlodinowom. Knjiga koja pokriva glavna pitanja o prirodi i porijeklu svemira objavljena je u rujnu. Prošlost je mogućnost Prema Hawkingu, jedna posljedica teorije kvantne mehanike jest da se događaji u prošlosti koji nisu direktno promatrani nisu dogodili na definitivan način. Umjesto toga, dogodili su se na sve moguće načine. Ovo je povezano s promjenjivom prirodom materije i energije koju zastupa kvantna mehanika: Osim ako ne dolazi do stimuliranog utjecaja izvana, stvari će zauzeti stanje nestabilnosti. Na primjer, ako je sve što poznajemo čestica koja putuje s točke A na točku B, onda nije istina da je uzela točno određeni put. Umjesto toga čestica će odabrati svaki mogući put kao bi povezala dvije točke. Autori pojašnjavaju: "Bez obzira koliko naše promatranje sadašnjosti bilo temeljito, prošlost, kao i budućnost su nedefinirane te postoje samo kao spektar mogućnosti." Teorija svega Ako postoji teorija koja može opisati cijeli svemir, onda je to M-teorija. Ovaj model je verzija teorije struna, koja navodi kako na najmanjem nivou sve čestice su zapravo maleni prstenovi koji vibriraju na različitim frekvencijama. Ako je to istina, sva materija i energija će pratiti pravila koja proizlaze iz prirode ovih struna. "M-teorija je jedini model koji posjeduje sve što konačna teorija treba imati", smatra Hawking. Jedna posljedica ove teorije jest da naš svemir nije jedini - postoje brojni svemiri s različitim fizičkim zakonima. Iskrivljena realnost Prije par godina, vlasti talijanskog grada Monze, zabranile su vlasnicima zlatnih ribica držanje u okruglim akvarijima. Svrha zakona bila je zaštititi jadne ribice od iskrivljenog pogleda na realnost, s obzirom da akvariji takvog oblika zakrivljuju svjetlost zbog čega ribica ne raspoznaje dobro okolinu. Hawking koristi ovaj primjer kako bi ukazao da je nemoguće znati pravu prirodu realnosti. Mislimo da imamo ispravnu sliku stvarnosti, no kako znamo da metaforički ne živimo u divovskom akvariju, s obzirom da nikad nismo bili u mogućnosti vidjeti izvan našeg aspekta gledanja radi usporedbe? Pitagora je ukrao formulu Hawking navodi kako slavni grčki matematičar Pitagora zapravo nije otkrio poznati poučak. Malo istraživanja sugerira kako je formula koja opisuje odnos među stranicama pravog trokuta, bila poznata od ranije. Babilonci su dokumentirali ideju u drevnim matematičkim spisima mnogo prije nego što je Pitagora stupio na scenu. Svemir je sam svoj stvaratelj Jedan od navoda iz knjige, koji je izazvao najveće debate, jest da ne trebamo ideju Boga kako bi objasnili postanak svemira. Umjesto njega, zakoni fizike mogu objasniti početak. Moderno razumjevanje vremena sugerira da je ono samo jedna dimenzija, poput svemira. Zbog toga nema početka. "S obzirom da postoji zakon gravitacije, svemir se može stvoriti iz ničega. Spontana kreacija razlog je zašto nešto postoji umjesto da ne postoji, te zašto postoji svemir, kao i mi u njemu", objašnjava Hawking.