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This question of accounting for what we call the "big bang state" -- the search for a physical explanation of it -- is probably the most important question within the philosophy of cosmology, and there are a couple different lines of thought about it.

One that's becoming more and more prevalent in the physics community is the idea that the big bang state itself arose out of some previous condition, and that therefore there might be an explanation of it in terms of the previously existing dynamics by which it came about

The problem is that quantum mechanics was developed as a mathematical tool. Physicists understood how to use it as a tool for making predictions, but without an agreement or understanding about what it was telling us about the physical world. And that's very clear when you look at any of the foundational discussions. This is what Einstein was upset about; this is what Schrodinger was upset about. Quantum mechanics was merely a calculational technique that was not well understood as a physical theory. Bohr and Heisenberg tried to argue that asking for a clear physical theory was something you shouldn't do anymore. That it was something outmoded. And they were wrong, Bohr and Heisenberg were wrong about that. But the effect of it was to shut down perfectly legitimate physics questions within the physics community for about half a century. And now we're coming out of that

The challenges for alternative gravity theories—collectively known as modified Newtonian dynamics, or MOND—were spelled out in a separate preprint coincidentally published the day after the new model appeared. Chief among them is recasting the leading role dark matter plays in drawing the universe together, as described by a well-established cosmological model known as LCDM, or Lambda cold dark matter.

Simply put, LCDM says that we wouldn’t be here without dark matter. The infant universe was so smooth that the gravitational attraction of ordinary matter alone wouldn’t have been enough to gather particles into galaxies, stars, and planets. Enter dark-matter particles. Under the LCDM model, their collective bulk sculpts normal matter into the modern cosmic structures studied by astronomers.

LCDM became the standard model of cosmology in part because it so precisely agrees with the CMB. This map of the early universe shows almost imperceptibly thick and thin spots rippling through the cosmos. More recently, researchers have been able to measure the orientation or polarization of the CMB’s light more precisely. Any successful cosmology will need to establish a comprehensive history of the cosmos by reproducing these three observations: the CMB’s temperature, the CMB’s polarization, and the current distribution of galaxies and galaxy clusters.

It all began when Warren Gefter, a radiologist “prone to posing Zen-koan-like questions,” asked his 15-year-old daughter, Amanda, over dinner at a Chinese restaurant near their home just outside Philadelphia: “How would you define nothing?”

“I think we should figure it out,” he said. And his teenage daughter — sullen, rebellious, wallowing in existential dread — smiled for the first time “in what felt like years.” The project proved to be a gift from a wise, insightful father. It was Warren Gefter’s way of rescuing his child.

Tracking down the meaning of nothing — and, by extension, secrets about the origin of the universe and whether observer-independent reality exists — became the defining project of their lives. They spent hours together working on the puzzle, two dark heads bent over their physics books far into the night.

As recent advances in cosmology suggest, the laws of gravity and quantum theory allow universes to appear spontaneously from nothing. Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist. It is not necessary to invoke God to light the blue touch paper and set the universe going.Our universe seems to be one of many, each with different laws. That multiverse idea is not a notion invented to account for the miracle of fine tuning. It is a consequence predicted by many theories in modern cosmology. If it is true it reduces the strong anthropic principle to the weak one, putting the fine tunings of physical law on the same footing as the environmental factors, for it means that our cosmic habitat—now the entire observable universe—is just one of many. Each universe has many possible histories and many possible states. Only a very few would allow creatures like us to exist. Although we are puny and insignificant on the scale of the cosmos, this makes us in a sense the lords of creation.

Infinity has its own special symbol: ∞. The symbol, sometimes called the lemniscate, was introduced by clergyman and mathematician John Wallis in 1655. The word "lemniscate" comes from the Latin word lemniscus, which means "ribbon," while the word "infinity" comes from the Latin word infinitas, which means "boundless."

Of all Zeno's paradoxes, the most famous is his paradox of the Tortoise and Achilles. In the paradox, a tortoise challenges the Greek hero Achilles to a race, providing the tortoise is given a small head start. The tortoise argues he will win the race because as Achilles catches up to him, the tortoise will have gone a bit further, adding to the distance.

Pi as an Example of Infinity Pi is a number consisting of an infinite number of digits. Jeffrey Coolidge / Getty Images Another good example of infinity is the number π or pi. Mathematicians use a symbol for pi because it's impossible to write the number down. Pi consists of an infinite number of digits. It's often rounded to 3.14 or even 3.14159, yet no matter how many digits you write, it's impossible to get to the end.

Some of the classic arguments for God’s existence have been largely abandoned, others have been refined, and new arguments or points about arguments do regularly appear.

The ontological argument, for instance, purports to prove the existence of a perfect being; the cosmological argument purports to prove the existence of a necessary or eternal Creator; the teleological argument purports to prove the existence of a Creator concerned with humanity.

If God exists then we also have an incentive, not to mention a moral duty, to fulfil this purpose; our eternal fate hangs on whether we follow God, as we were created to, or rebel against his authority.

science is only a small part of human capability. We gain knowledge of our place in the universe not only from science but also from history, art, and literature. Science is a creative interaction of observation with imagination. “Physics at the Fringe” is what happens when imagination loses touch with observation. Imagination by itself can still enlarge our vision when observation fails. The mythologies of Carter and Velikovsky fail to be science, but they are works of art and high imagining. As William Blake told us long ago, “You never know what is enough unless you know what is more than enough.”

Over most of the territory of physics, theorists and experimenters are engaged in a common enterprise, and theories are tested rigorously by experiment. The theorists listen to the voice of nature speaking through experimental tools. This was true for the great theorists of the early twentieth century, Einstein and Heisenberg and Schrödinger, whose revolutionary theories of relativity and quantum mechanics were tested by precise experiments and found to fit the facts of nature. The new mathematical abstractions fit the facts, while the old mechanical models did not.

String cosmology is different. String cosmology is a part of theoretical physics that has become detached from experiments. String cosmologists are free to imagine universes and multiverses, guided by intuition and aesthetic judgment alone. Their creations must be logically consistent and mathematically elegant, but they are otherwise unconstrained.

Nature is not always so kind, however. Fields like particle physics and cosmology sometimes include good theories that fit all the data but nevertheless seem unsatisfying to us.

Faced with theories that fit all the data but seem unnatural, one can certainly shrug and say, “Maybe that’s just the way it is.” But most physicists take the attitude that almost none of our current models are exactly correct; our best ideas are still approximations to the underlying reality. In that case, apparent fine-tunings can be taken as potential clues that might prod us into building better theories.

Rather than predicting definite outcomes, we attach probabilities to members of an ensemble of many different experimental outcomes.

The universe is unimaginably big, and it keeps getting bigger. But astronomers cannot agree on how quickly it is growing — and the more they study the problem, the more they disagree.

Some scientists call this a “crisis” in cosmology. A less dramatic term in circulation is “the Hubble Constant tension.”

Nine decades ago, the astronomer Edwin Hubble showed that the universe is orders of magnitude vaster than previously imagined — and the whole kit and kaboodle is expanding. The rate of that expansion is a number called the Hubble Constant.

All scientific results are, of course, subject to revision and refutation by later experiments. The problem comes when these replications don’t occur and the information keeps spreading unchecked. Continue reading the main story Related Coverage Raw Data: Hills to Scientific Discoveries Grow SteeperFEB. 17, 2014 Raw Data: New Truths That Only One Can SeeJAN. 20, 2014 D

Based on the number of papers in major journals, Dr. Ioannidis estimates that the field accounts for some 50 percent of published research.

Together that constitutes most of scientific research. The remaining slice is physical science — everything from geology and climatology to cosmology and particle physics. These fields have not received the same kind of scrutiny as the others. Is that because they are less prone to the problems Dr. Ioannides describe

In earlier columns, I have defended time from the assaults of physics. With a few exceptions, physicists have not been kind to time. Relativity theory stripped it of its tenses, dismissing the difference between past, present, and future as illusory. Worse, the theory seemed to deny time an independent existence.

My own view, however, is that both space and time are traduced in physics. They should form a victim support group, which is why this column is devoted to a defence of space.

Places – habitats – are stripped down to decimal places. Much is lost in consequence. The space of the physicist has neither ‘here’ nor ‘there’, no centre or periphery, no inside or outside, except in terms of relationships between points defined mathematically with respect to a frame of reference built out of axes whose (0,0,0) point of origin is arbitrarily chosen. The inhabitants of the physicists’ space are fields and objects that have only primary qualities – size, distance, number of instances. They are void of secondary qualities – warmth, brightness, colour, texture – never mind meaning, value, and use – even though all these qualities are inseparable from the space in which we experience, enact, and suffer our lives.

seen traces of what could be a new fundamental particle of nature.

One possibility, out of a gaggle of wild and not-so-wild ideas springing to life as the day went on, is that the particle — assuming it is real — is a heavier version of the Higgs boson, a particle that explains why other particles have mass. Another is that it is a graviton, the supposed quantum carrier of gravity, whose discovery could imply the existence of extra dimensions of space-time.

At the end of a long chain of “ifs” could be a revolution, the first clues to a theory of nature that goes beyond the so-called Standard Model, which has ruled physics for the last quarter-century.

As the title suggests, Kaku’s latest concern is with what he calls the “holy grail” of all science, the metaphorical “umbilical cord” of our infant universe, whenever it was (or wasn’t) born out of the alleged multiverse. He wanted to write a balanced account of the physics community’s quest to prove string theory — and thus to resolve the messy, imperfect Standard Model of subatomic particles into one elegant theory of everything

This book is like a State of the Union where the union is all of existence.

Right now the known laws of the universe — “the theory of almost everything,” he calls it — can be written on a single sheet of paper. There’s Einstein’s general relativity on one line, and then a couple more for the Standard Model. “The problem is that the two theories hate each other,” he said. “They’re based on different math, different principles. Every time you put them together it blows up in your face. Why should nature be so clumsy?”

Mysterious fast radio bursts have been used to unlock another strange aspect of the universe: the case of the "missing matter."

Astronomers have yet to determine what causes these fast radio bursts, which are unpredictable but can be spotted and traced back to their origin using sensitive telescopes.

Normal matter, called baryonic matter in this study, is made of the protons and neutrons that comprise both humans and star stuff. But astronomers could only account for about half of it that should exist in the universe.