Any model which agrees with observation is of equal value to any likewise model. No such model can be said to be more real than any other such model. Models are evaluated in terms of simplicity and their ability to make clear, falsifyable preditions.
The heliocentric model of Johannes Kepler can not be said to be more 'real' than the much older geocentric model of Ptolemy. Both agree with observation, although the heliocentric model is much more elegant in its explanation.
Our being restricts the environments we could potentially find ourselves in. We could not exist in a solar system with two suns, and thus find ourselves in a system with a single sun. This type of deduction is called 'weak anthropic principle'.
The habitable zone of a star ('Goldilocks Zone') is determined by the size and temperature of the star. A planet too close will be too hot for life; those beyond the zone too cold.
Physicist John Wheeler considered replicating the double-slit experiment with photons from a distant quasar. Whether we observe or not (thus altering the resulting inference pattern) will impact light that emerged even before our sun came to exist.
Ever thought about the dimensions of the big bang? No? Try to imagine a coin of one centimeter diameter suddenly blowing up to ten million times the width of the Milky Way.
Feynman assumes that particles at microscopic scale travel from A to B by taking every possible path - simultaneously. This accounts for the inference patterns observed in the double slit experiment.
According to Feynman, a particle samples every path connecting point A and B, hence collecting information about the path to be taken. Manipulation of the experiment, e.g. closing one of the slits, will change information collected and the result observed.
Information about each path can be imagined as a vector, called phase. Different phases can enhance or diminish each other. Adding up all the phases enables us to calculate the probability of the particle reaching point B.
Humanity's role in the universe is in no way central or privileged. Despite this, only a very narrow range of possible universes could support organisms as complex as humans. We had a great influence on creation - indirectly.
In 1929, Edwin Hubble deducted that the universe must be expanding. Recession speed increases with distance. The extrapolation of this idea into the distant past lead to the big bang hypothesis.
To better visualize the expansion and increasing speed of recession, imagine all galaxies on the surface of an inflating baloon. After a certain time, a galaxy near the observer will have moved less than an already very distant galaxy.
Universes appear randomly due to quantum fluctuations. Most collapse after a fraction of time, a few inflate to critical size. All universes start off in a very similar way, each with all possible histories ahead of them. In later stages, different universes differ immensely.
Adding up all energies within the universe, the resulting number must be zero. Bodies not requiring any energy to assemble can appear entirely at random.
Inside a sufficiently inflated universe, space is locally stable. This dictates that any isolated body surrounded by empty space must have a positive energy total. In other words: To assemble this body, work has to be done.
In the very early universe, there were four dimensions of space and none of time. Time is a modified space dimension. To ask what came before the beginning of the universe is as meaningless as asking what is south of the South Pole.
General theory of relativity illustrates that time and space are not independant. Once quantum effects are taken into account, time can be warped to an extent that it behaves identical to another space dimension. This requires an extreme scenario, e.g. the big bang.
Moving clocks run more slowly than unmoved clocks ('Time dilation'). This also applies to biological clocks, making moving people age more slowly. However, this effect is only noticeable at extremely high velocities, such as 50% of light speed.
The strong anthropic principle suggests that our existence imposes not only constraints on the environment we live in, but also on the utmost fundamental form and content of the laws of nature themselves.
Not only planet Earth, but also the configuration of our solar system and the design of the fundamental laws of nature of our universe seem oddly conductive to human life. The tiniest variation in any law of nature would lead to an entirely inanimate universe.
1. GravityThe weakest of the four forces. Its long range implies that all objects in the universe attract each other. For large bodies, gravitational forces can dominate over all other forces because they are additive.
2. ElectromagnetismThis force is much stronger than gravity while also operating at long range. It requires affected particles to be electrically charged. Biology and chemistry are the result of electromagnetic interactions.
3. Weak nuclear forceThis force causes radioactivity. It played a central role in the formation of elements in stars during the early stages of the universe. There is no contact with this force in everyday life.
4. Strong nuclear forceThis force binds the components of atomic nuclei together. The strong nuclear force is the energy source for stars and nuclear power facilities. As with the weak force, we experience no direct contact with it.
M-Theory is a network of domain specific theories to explain every aspect of the universe. Whenever there is overlap, overlapping theories have to agree on observations made. Hence, M-Theory can be treated as a single theory.
Now, [...] faced with scientific claims like [...] the multiverse hypothesis [...], the Catholic Church will again defend human nature by proclaiming that the immanent design in nature is real.
The most incomprehensible thing about the universe is that it is comprehensible.
Also known as the Buckyball experiment, Austrian researchers shot molecules through a barrier with two slits. Results did not agree with Newtonian physics but instead showed an inference pattern resembling expected results for light waves.
On an atomic scale, all particles exhibit features known from the wave/particle duality of light. Everyday Newtonian physics can not explain observations on a microscopic scale but approximate results on macroscopic scales.