All posts tagged: Physics

Steady State Theory

Steady State Theory was a theory proposed in twentieth-century cosmology to explain evidence that the universe was expanding, but still retain the core idea that the universe always looks the same, and is therefore unchanging in practice (and has no beginning and no end). This idea has largely been discredited due to astronomical evidence that suggests the universe is, in fact, changing over time. STEADY STATE THEORY BACKGROUND AND DEVELOPMENT When Einstein created his theory of general relativity, early analysis showed that it created a universe that was unstable — expanding or contracting — rather than the static universe that had always been assumed. Einstein also held this assumption about a static universe, so he introduced a term into his general relativity field equations called the cosmological constant, which served the purpose of holding the universe in a static state. However, when Edwin Hubble discovered evidence that distant galaxies were, in fact, expanding away from the Earth in all directions, scientists (including Einstein) realized that the universe didn’t seem to be static and the term …

Physics of bubbles can tell us about language

What do the physics of bubbles have in common with the way you and I speak? Not a lot, you might think. But my recently published research uses the physics of surface tension (the effect that determines the shape of bubbles) to explore language patterns – where and how dialects occur. This connection between physical and social systems may seem surprising, but connections of this kind have a long history. The 19th century physicist Ludwig Boltzmann spent much of his life trying to explain how the physical world behaves based on some simple assumptions about the atoms from which it is made. His theories, which link atomic behaviour to the large scale properties of matter, are called “statistical mechanics”. At the time, there was considerable doubt that atoms even existed, so Boltzmann’s success is remarkable because the detailed properties of the systems he was studying were unknown. The idea that details don’t matter when you are considering a very large number of interacting agents is tantalising for those interested in the collective behaviour of large …

Quantum consciousness

The mere mention of “quantum consciousness” makes most physicists cringe, as the phrase seems to evoke the vague, insipid musings of a New Age guru. But if a new hypothesis proves to be correct, quantum effects might indeed play some role in human cognition. Matthew Fisher, a physicist at the University of California, Santa Barbara, raised eyebrows late last year when he published a paper in Annals of Physics proposing that the nuclear spins of phosphorus atoms could serve as rudimentary “qubits” in the brain—which would essentially enable the brain to function like a quantum computer. As recently as 10 years ago, Fisher’s hypothesis would have been dismissed by many as nonsense. Physicists have been burned by this sort of thing before, most notably in 1989, when Roger Penrose proposed that mysterious protein structures called “microtubules” played a role in human consciousness by exploiting quantum effects. Few researchers believe such a hypothesis plausible. Patricia Churchland, a neurophilosopher at the University of California, San Diego, memorably opined that one might as well invoke “pixie dust in …

Dark Energy, What it could be?

One of the shocking revelations of the late 20th Century was that the universe was expanding at an accelerating rate. Before that mysterious “speed-up” was discovered, people thought that the rate must be slowing down as the universe expanded. What’s worse, at the time of discovery, there was no known mechanism to explain how the expansion of the universe could be accelerating. Guess what! There still isn’t a well-explained one. But, at least whatever it is has a name. This mysterious driving force is known as Dark Energy. There are a few possibilities of what it could be. IS DARK ENERGY A PROPERTY OF SPACE-TIME? General relativity is often thought of as a theory of gravity, mostly because this is its greatest application as it explains the dynamics of objects in accelerating reference frames (like a gravitational field). However, general relativity is more than that, and it has far reaching implications into the vary nature of the universe. One of the most amazing consequences of Einstein’s theory is that empty space isn’t really empty. In fact, empty …

Black Holes, A Brief Introduction

Everybody has heard of black holes. Science fiction books and movies use them as great plot devices. However, does everybody know what they actually are? These real-life objects are scattered throughout the universe, particularly at the centers of galaxies. So, they’re common, but nobody has really explored them! There’s a good reason for that: once you get inside a black hole, there’s no escape. That makes them intriguing and frightening all at once. However, that hasn’t stopped astronomers from studying them from the outside and using the laws of physics to understand them. Black holes are objects in the universe with so much mass trapped inside their boundaries that they have incredibly strong gravitational fields. That gravity is so strong that nothing can escape a black hole once it has gone inside. Most black holes contain many times the mass of our Sun and the heaviest ones can have millions of solar masses. Despite all that mass, the actual singularity that forms the core of the black hole has never been seen or imaged. The …

Skeptic Society Magazine Women Leading Science Maths and Physics

19 Women Leading Math and Physics

In an interview with Quanta Magazine last fall, the eminent theoretical physicist Helen Quinn recalled her uncertainty, as a Stanford University undergraduate in the 1960s, about whether to pursue a career in physics or become a high school teacher. “There were no women in the faculty at Stanford at that time in the physics department,” Quinn said. “I didn’t see myself there.” Her adviser warned her that “graduate schools are usually reluctant to accept women because they get married and they don’t finish.” (He kindly added that “I don’t think we need to worry about that with you.”)In the 1970s, the Italian-American dark matter physicist Elena Aprile survived male advisers with a similar unwillingness to tolerate competing demands on her time. “It made me of titanium,” she said of her relationship with her brilliant but demanding mentor. “He would keep pushing you beyond the state that is even possible: ‘It’s all about the science; it’s all about the goal. … You have a baby to feed? Find some way.’”Four decades later, the welcome mat can still be hard to locate. “In …