One of my great discoveries on the early Internet was the amount of information about the Milky Way. I hadn’t come across anything that really described its size, behaviour, composition, and our place in all of that. However, back about 2005 or so, I devoured information about it, and as I did so, more and more new discoveries were made.

I recently discovered this love site, Pics About Space, where much of what I had been learning has been visualized. Now that we have 1-2 trillion galaxies in mind, I look forward to new images.

The more we discover about the universe, the more astounding it turns out to be. One thing is for certain – it is incomprehensible in its vastness. We believe that there is much of it that we will never discover beyond the visible universe. Such are the restrictions put upon us by the speed of light. As we look further away from earth, we also look further back in time, which means that we can only look as far away as the universe is old.

Spacetime and relativity in action.

Those are Galaxies, not Stars.

to get a better perspective on it, check out the following video (add your own soundtrack). Provided by the Sloan Digital Sky Survey.

music of the strings – who’s ever heard of an orchestra with a spheres section?

The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory by Brian Greene

Part I – The Edge of Knowledge Ch 1 – Tied Up with String

p15-6
“… particle properties in string theory are the manifestation of one and the same physical feature: the resonant pattern of vibration – the music, so to speak – of fundamental loops of string.”

p17
“The discovery of the [Theory of Everything aka T.O.E.] – … – would provide the firmest foundation on which to build our understanding of the world. It’s discovery would mark a beginning, not an end.”

Part II – The Dilemma of Space, Time, and the Quanta Ch 2 – Space, Time, and the Eye of the Beholder

p25
“The most accurate measuring devices in the world confirm that space and time – as measured by distances and durations – are not experienced identically by everyone.”

“Special relativity is not in our bones – we do not feel it.”

p32
“Regardless of relative motion between the source of photons and the observer, the speed of light is always the same.”

p50
“Einstein proclaimed that all objects in the universe are always traveling through spacetime at one fixed speed – that of light.”

p51
“… light does not get old; a photon that emerged from the big bang is the same age today as it was then. There is no passage of time at light speed.”

p52
[re: muon particle accelerated to near light speed]
“Since the mass of the muon increases without limit as its speed approaches that of light, it would require a push with an infinite amount of energy to reach, or to cross the light-barrier.”

Ch 3 – of Warps and Ripples

p61
“… gravity is mysterious. It is a grand force permeating the life of the cosmos, but it is elusive and ethereal.”

p67
“Gravity, according to Einstein, is the warping of time and space.”

p69-70
“In Einstein’s view, the gravitational tether holding the earth in orbit… is the warping of the spacial fabric caused by the Sun’s presence. [mass]”

p70-1
“Moreover, each of us – like any massive object – also warps the spacial fabric in close proximity to our bodies, although the comparatively small mass of a human body makes this a miniscule indentation.”

p72
quoting John Wheeler
“mass grips space by telling it how to curve, space grips mass by telling it how to move.”

p73
“… the mathematics of general relativity shows that in the case of a relatively slow-moving body like the earth revolving around a typical star like the sun, the warping of time actually has a far more significant impact on the earth’s motion than does the warping of space.”

p73
“When no mass is present, space is flat… if a large mass comes on the scene, space will warp, … spread outward from the massive body [like ripples], ultimately settling down into a warped shape that communicates the pull of the new body.”

p74
“… Einstein was able to calculate how fast disturbances to the fabric of the universe travel… precisely the speed of light…”

p75
“… the closer [one] gets to the sun the slower [one’s] clock will run. It is in this sense that gravity distorts time as well as space.”

“… feeling accelerated motion is the same as feeling gravitational force…”

p81
“…. mounting evidence indicates that there is a very massive black hole, some two and a half million times as massive as the sun, sitting in the center of our own Milky Way galaxy.”

quasars
“black holes of whose masses may well be billions of times that of the sun.”

p82
“… either the fabric of the universe is stretching or it is shrinking, but it is not simply staying put. The equations of general relativity show this explicitly.”

p83
“… there s simply no space outside the primordial pin point… Instead, the big bang is the eruption of compressed space whose unfurling, like a tidal wave, carries along matter and energy even to this day.”

Ch 4 – Microscopic Weirdness

p104
“… all matter has wave-like character.”
Ch 5 – The Need for a New Theory: General Relativity vs Quantum Mechanics

Part III – The Cosmic Symphony Ch 6 – Nothing but Music: the Essentials of Superstring Theory

p141
“… the length of a typical string loop is about the Planck length…”

p143
“Just as the different vibrational patterns of a violin string give rise to different musical notes, the different vibrational patterns of a fundamental string give rise to different vibrational masses and force charges.”

p143-4
“According to string theory, the properties of an elementary ‘particle’ – its mass and its various force charges – are determined by the precise resonant pattern of vibration that its internal string executes.”

p149
“… the Planck mass; it’s about equal to the mass of a grain of dust or a collection of a million average bacteria. And so, the typical mass-equivalent of a vibrating loop in strin gtheory is generally some whole number times the Planck mass. Physicists often express this by saying that the ‘natural’ or ‘typical’ energy scale (and hence mass scale) of string theory is the Planck scale.”

p165
“… even though they are spatially extended they can be described consistently in the framework of quantum mechanics… [A]mong the resonant vibrational patterns there s one that has the exact properties of the graviton, thus ensuring that the gravitation force is an intrinsic part of its structure.”

Ch 7 – The “Super” in Superstrings

p171
“… every electron in the universe, always and forever, spins at one fixed and never changing rate.”

Ch 8 – More Dimension than Meets the Eye

9 or 10 dimensions of Space, 1 dimension of Time
3 sensory dimensions, 6 or 7 infrasensory dimensions

p206
“… extradimensional geometry determines fundamental physical attributes like particle masses and charges that we observe in the usual three large space dimensions of common experience.”

“According to string theory, the universe is made up of tiny strings whose resonant patterns of vibration are the microscopic origin of particle masses and force charges. String theory also requires extra space dimensions that must be curled up to a very small size to be consistent with our never having seen them.”

“… the fundamental properties of the universe are determined, in large measure, by the geometrical size and shape of the extra dimensions.”

Calabi-Yau Manifold
Ch 9 – The Smoking Gun: Experimental Signatures

p222
“… a fundamental property of string theory is that it is highly symmetric, incorporating not only intuitive symmetry principles but respecting as well, the maximal mathematical extension of these principles, supersymmetry.”

Part IV – String Theory and the Fabric of Spacetime Ch 10 – Quantum Geometry

p232
“On scales as small as a Planck length, a new kind of geometry must emerge, one that aligns with the new physics of string theory. This new geometrical framework is called quantum geometry.”

p239
[re: Garden-hose shaped 2-d universe with superstrings wound around it]
“The new possibility of wound-string configurations implies that the energy of a string in a Garden-hose universe comes from two sources: vibrational motion and winding energy.”

p240
“… it proves convenient to separate the vibrational motion of strings into two categories: uniform and ordinary vibrations. Ordinary vibrations refer to the usual oscillations…; uniform vibrations refer to even simpler motion: the overall motion of string as it slides from one position to another without changing its shape.”

“All string motion is a combination of sliding and oscillating – of uniform and ordinary vibrations.”

“First, uniform vibrational excitations of a string have energies that are inversely proportional to the radius of the circular dimension.”

“Second…, the winding mode energies are directly – not inversely – proportional to the radius.”

“These two observation establish that large valves of the radius imply large winding energies and small vibration energies, whereas small values of the radius imply small winding energies and large vibration energies.”

p240-1
“… For any large circular radius of a Garden-hose universe, there is a corresponding small circular radius for which the winding energies of strings in the former universe equal the vibration energies of strings in the latter, and vibration energies of strings in the former equal winding energies of strings in the latter. As physical properties are sensitive to the total energy of a string configuration – … – there is no physical distinction between these geometrically distinct forms for the Garden-hose universe.”

p241
“… string theory claims that there is no difference whatsoever between a ‘fat’ Garden-hose universe and a ‘thin’ one.”

p249
“… if the spatial shape of a dimension is circular, there are two different yet related operational definitions of distance in string theory.”

p249-50
“The first definition uses strings that are not wound around circular dimension, whereas the second definition uses strings that are wound.”

p251
“According to the light string modes, the universe is large and expanding; according to the heavy modes it is tiny and contracting.”

p255
“… it might be possible for two different Calabi-Yau shapes, chosen for the extra curled-up dimensions in string theory, to give rise to identical physics.”

p259
“… mirror symmetry proclaims that particular pairs of Calabi-Yau spaces, pairs that were previously thought to be completely unrelated, are now intimately connected by string theory.”

Ch 11 – Tearing the Fabric of Space

p264
“A wormhole… is a bridge or tunnel that provides a shortcut from one region of the universe to another.”

wormhole

p265
“Black holes provide another compelling example in which the fabric of space is stretched to its limit.
Ch 12 – Beyond Strings: In Search of M-Theory

p287
“First, M-theory has eleven dimensions (ten space and one time).”

“The second feature… is that it contains vibrating strings, but it also includes other objects: vibrating two-dimensional membranes, undulating three-dimensional blobs (called “three-branes”)…”

Ch 13 – Black Holes: A String / M-Theory Perspective

p321
“… distinguishing features? One… is the black hole’s mass… Research has revealed that [others] are the electric and certain other force charges a black hole can carry, as well as the rate at which it spins.”

“… mass, force charges, and spin- … distinguish one elementary particle from another.”

“The similarity of the defining traits has led a number of physicists over the years to the strange speculation that black holes might actually be giant elementary particles.”

p331
“… the new massless pattern of string vibration arising from the space-tearing conifold transition is the microscopic description of a massless particle into which the black hole was transmuted.”

“… as a Calabi-yau shape goes through a space-tearing conifold transition, an initially massive black hole becomes every lighter until it is massless and then it transmutes into a massless particle – such as a massless photon – which in string theory is nothing but a single string executing a particular vibrational pattern.”

p332
“… [studied] kinds of black holes… and elementary particles are actually two phases of the same underlying stringy material.”

Ch 14 – Reflections on Cosmology

Part V – Unification in the Twenty-First Century
Ch 15 – Prospects