Philosophical Context of Design: The Fabric of the Cosmos

THE FABRIC OF THE COSMOSSPACE, TIME, AND THE TEXTURE OF REALITY

Brian Greene

Philosophical Context of Design, Fall 2011Alison W. Tisza

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WHAT IS REALITY?

Surely, reality is what we think it is; reality is revealed to us by our experiences.

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WHAT IS REALITY?

Surely, reality is what we think it is; reality is revealed to us by our experiences.

This is the view that many of us hold, if only implicitly.

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WHAT IS REALITY?

Surely, reality is what we think it is; reality is revealed to us by our experiences.

This is the view that many of us hold, if only implicitly.

However, science will tell us that the human experience is often a misleading guide to the true nature of reality.

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CAN WE KNOW REALITY?

Democritus knew that the knowledge of truth would be difficult.

Perception through the senses is subjective and the derived interpretations are different for each person.

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CAN WE KNOW REALITY?

Plato stated that knowledge is justified true belief.

However, he argues that knowledge is proportionate to the realm from which it is attained.

Only if an account is derived through a stable and unchanging lens can it be knowledge; otherwise it is opinion.

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AN “ABSURD” REALITY?

Albert Camus postulated that the absurd arises when the human need to understand meets the unreasonableness of the world.

“Appetite for the absolute and for unity” meets “the impossibility of reducing this world to a rational and reasonable principle.”

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THE MYTH OF SISYPHUS

Sisyphus is condemned to eternal repetition of the same meaningless task - rolling a boulder up a hill only to watch it roll back down again.

Only by acknowledging the truth of the situation is he freed. He is no longer bound by a need to pursue life’s purpose or create meaning.

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CAN THERE BE MEANING IN EXISTENCE?

Kierkegaard and Nietzsche saw the human experience as subjective, therefore the individual is responsible for giving his or her life meaning and for living that life passionately and sincerely.

Existential heroes, such as the Knight of Faith and the Übermensch, define the nature of their own existence.

Existence stems from the Latin existere, meaning to stand out or to come into being.

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THE ULTIMATE QUESTION

What is life’s value?

Physical reality both sets the arena and provides the illumination for grappling with this question. By deepening our understanding of the true nature of physical reality we both reconfigure our sense of ourselves and our experience of the universe.

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REALITY & THE SPINNING BUCKET

1. The surface of the water starts out flat.

2. The surface remains flat as the bucket starts to spin.

3. The water starts to spin and the surface becomes concave.

4. Remains concave while the water spins, even as the bucket slows and stops.

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REALITY & THE SPINNING BUCKET

Why does the water take this shape?

What does it mean that the water is spinning?

Spinning with respect to what?

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WHAT IS SPACE?

Nonentity Entity

Relative

Not relative

NEWTON - Absolutist position.

Space is an entity. Accelerated motion is not relative.

LEIBNIZ - Relationist position.

Space is not an entity. All aspects of motion are relative.

Space has no meaning beyond providing the natural language for discussing the relationship between one object’s location and another.

MACH - Relationist position.

Space is not an entity. Accelerated motion is relative to average mass distribution in the universe.

EINSTEIN (SPECIAL RELATIVITY)

Space and time are individually relative. Spacetime is an absolute entity.

The combined speed of any object’s motion through space and its motion through time is always precisely equal to the speed of light. For example, as motion through space increases, motion through time decreases to keep the combined total unchanged.

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RELATIVITY REALITY

Spacetime is like a flipbook with an expanded binding:

It gives us the time that an event occurred - the page of the book. The location of the region within space is depicted on the page.

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RELATIVITY OF SIMULTANEITY

Spacetime can be divided into different, equally valid slices. Observers moving relative to each other will cut spacetime differently. As a result, the observers will not agree on what things happen simultaneously.

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SPACETIME SLICES

Spacetime is sliced at different angles by observers in relative motion. The greater the relative speed, the greater the angle, with a maximum angle of 45º (corresponding to the maximum speed set by light).

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WARPED SPACETIME SLICES

Since gravity and acceleration are equivalent, an accelerated observer carves spacial slices that are warped and curved.

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THE RELATIVITY CONSENSUS IS...?

Space and time are in the eye of the beholder.

There is no single, preferred universal clock or universal yardstick. No consensus on what constitutes a here and now.

The clock is your clock. The story is your story.

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QUANTUM REALITY

Two spheres resting and separated by a vast distance in space.

The spheres exist in a reality in which things hover in a haze of being partly one way and partly another. In this case, the spheres hover between blinking either purple or orange.

In quantum mechanics, we can never be completely certain. The best that we can ever do is predict the probability of an outcome.

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QUANTUM POSSIBILITIES

Things become definite only when a suitable observation forces them to relinquish quantum possibilities and settle on an outcome. Reality is ambiguous until perceived.

And for the spheres changing instantaneously, there can be an instantaneous bond between what happens at two widely separate locations.

Instantaneous, matching change in the color of both spheres.

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QUANTUM PARADOX

Before measurement the sphere does not have a definite location. Rather, the act of measurement creates the very reality that it is measuring.

As the sphere moves, it is impossible to know both the exact velocity and exact position.

Space

Time

50%

50%

Space

Time

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COSMOLOGY & TIME’S ARROW

The asymmetry of time - the distinction between going forward and backward - is a prevailing element of experiential reality.

If time exhibited the same symmetry with which we experience left and right or back and forth, the world would be unrecognizable.

Eggs break, they don’t unbreak; memories are of the past, never of the future.

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Nothing describes both large and small in a coherent way. When relativity and quantum mechanics are used together the result is nonsensical probabilities.

DIFFERENT TAKES ON REALITY

RELATIVITY for big things.

Newton’s and Einstein’s laws do a good job describing the universe as we perceive it.

Einstein

Newton

But diverge at extremes of speed and gravity.

Quantum Mechanics for small things.

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UNIFIED THEORY

Superstring theory is a pretty good contender for unified theory.

It postulates that all matter is merely energy filaments that vibrate at different patterns.

It reconciles relativist theory and quantum mechanics if we accept that there are nine spatial and one time dimension (versus our three spatial and one time dimension).

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M-THEORY

The more robust M-Theory postulates ten spatial dimensions and one time dimension, for a total of eleven.

The conclusion, we glimpse but a meager slice of reality.

The extra dimensions of spacetime are conjectured to take the form of a six dimensional Calabi-Yau manifold.

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REALITY & MEANING

So who’s right?

Camus: By relinquishing everything beyond immediate experience and ceasing to search for a deeper meaning, we will triumph.

Kierkegaard and Nietzsche: We create our own reality.

Feynman: To assess life and experience the universe on all levels, not just those immediately accessible to our senses, provides a more magnificent and enriched experience.

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REALITY & MEANING

Space

Space

Time

OBSERVER

PAST

FUTURE(Probabilities)

0.00000009%chance of chicken for dinner in Paris

0.005%chance of finding a pennyon the way to work

Perhaps if we are unobtrusively provided with information that helps us better understand our position in space and the probabilities of events in our past and future, we can focus on the immediate experience while making decisions to create and optimize our own reality.