Summary of Sean Carroll's Something Deeply Hidden

Everest Media

Description

Please note: This is a companion version & not the original book.
Sample Book Insights:
#1 Quantum mechanics is the heart and soul of modern physics, and it is used in everything from astrophysics to particle physics. It is the most comprehensive view of reality we have, and it is not magic.
#2 The world is fundamentally intelligible, and we have something of a mental block when it comes to quantum mechanics. We need to overcome this, and teach students that quantum mechanics is just a list of rules that we use to make predictions.
#3 The first is that quantum mechanics should be understandable, even if we’re not there yet. It is unique among physical theories in drawing an apparent distinction between what we see and what really is. But this challenge isn’t insuperable, and if we free our minds from certain old-fashioned and intuitive ways of thinking, we find that quantum mechanics isn’t hopelessly mystical or inexplicable.
#4 The third message is that all this matters, and not just for the integrity of science. The success of the existing adequate but not perfectly coherent framework of quantum mechanics shouldn’t blind us to the fact that there are circumstances under which such an approach simply isn’t up to the task.

Sujets

• Quantum theory
• Physics

Informations

• Publié par: Everest Media LLC
• Date de parution: 18 avril 2022
• Nombre de lectures: 0
• EAN13: 9781669386148
• Langue: English
• Poids de l'ouvrage: 1 Mo

Extrait

Insights on Sean Carroll's Something Deeply Hidden
Contents Insights from Chapter 1 Insights from Chapter 2 Insights from Chapter 3 Insights from Chapter 4 Insights from Chapter 5
Insights from Chapter 1

#1

Quantum mechanics is the heart and soul of modern physics, and it is used in everything from astrophysics to particle physics. It is the most comprehensive view of reality we have, and it is not magic.

#2

The world is fundamentally intelligible, and we have something of a mental block when it comes to quantum mechanics. We need to overcome this, and teach students that quantum mechanics is just a list of rules that we use to make predictions.

#3

The first is that quantum mechanics should be understandable, even if we’re not there yet. It is unique among physical theories in drawing an apparent distinction between what we see and what really is. But this challenge isn’t insuperable, and if we free our minds from certain old-fashioned and intuitive ways of thinking, we find that quantum mechanics isn’t hopelessly mystical or inexplicable.

#4

The third message is that all this matters, and not just for the integrity of science. The success of the existing adequate but not perfectly coherent framework of quantum mechanics shouldn’t blind us to the fact that there are circumstances under which such an approach simply isn’t up to the task.

#5

Most public discussions of quantum mechanics describe it as mysterious, weird, and bizarre. However, quantum mechanics is also inscrutable. It tempts us into projecting qualities and capacities onto it that aren’t there.

#6

The world is full of stuff, and how it behaves is a question that has been asked since people started asking questions. Physics is the study of change and motion, of both living and nonliving matter.

#7

Newton’s laws of motion are a classic example of classical mechanics. They explain how objects move in response to other objects and forces, and they can be used to catch baseballs or land rovers on Mars.

#8

The position and velocity of a classical system are its state. The set of all possible states that a system could have is its phase space. The French mathematician Pierre-Simon Laplace pointed out a profound implication of the classical mechanics way of thinking. In principle, a vast intellect could know the state of literally every object in the universe, from which it could deduce everything that would happen in the future.

#9

The enigma at the heart of quantum reality can be summed up in a simple motto: what we see when we look at the world is fundamentally different from what actually is.

#10

The state of a particle in quantum mechanics is not a location and a velocity, but a cloud of probability. The wave function of a particle assigns a specific number to every possible measurement outcome, and the amplitude of that outcome is the probability of getting that outcome when we perform the measurement.

#11

The state of a classical system is given by the position and velocity of each of its moving parts. To follow its evolution, we imagine something like the following procedure: 1. State the position and velocity of each moving part.

#12

The rules of standard textbook quantum mechanics come in two parts. In the first part, we have a structure that exactly parallels that of the classical case. Quantum systems are described by wave functions rather than by positions and velocities.

#13

The rules of quantum mechanics are similar to those of classical mechanics, except for one thing: measurement. When you perform a measurement on a quantum system, such as the position or spin of a particle, the result you get is only one of many possible outcomes. You can't predict which outcome you will get, but you can calculate the probability for each allowed outcome.

#14

The five rules of quantum mechanics are: 1) Measurements are fundamental. 2) The wave function associates an amplitude with every possible measurement outcome; the probability for any outcome is the square of that amplitude. 3) Upon measurement, the wave function collapses. 4) What we have instead is a recipe that we enshrine in textbooks and teach to our students.

#15

The laws of physics are not presented in a form that allows us to understand them. We can set up specific problems and answer them, but we can't explain what's happening behind the scenes. We do have a number of good ideas about what that could be, and it's past time that the physics community started taking these ideas seriously.

#16

The history of quantum mechanics is marked by a famous series of debates between Albert Einstein and Niels Bohr over how to think about it. Bohr, a Danish physicist, advocated an approach similar to the textbook recipe we discussed in the last chapter: use quantum mechanics to calculate the probabilities for measurement outcomes, but don’t ask of it anything more than that.

#17

After the success of the theory of statistical mechanics, which described the motion of large numbers of atoms and molecules, physicists began to think that quantum mechanics should be thought of as an epistemic theory rather than an ontological one.

#18

The most minimalistic version of quantum theory is to take the wave function seriously as a direct representation of reality, not just a bookkeeping device to help us organize our knowledge. We treat it as ontological, not epistemic.

#19

The wave function is not a bookkeeping device, but an exact representation of the quantum system. The world is a wave function, nothing more or less. We can use the phrase quantum state as a synonym for wave function.

#20

The reality of a quantum system is described by a wave function or quantum state, which is a superposition of every possible outcome of an observation. The quantum/ classical divide is a matter of personal convenience, not a fundamental aspect of nature.

#21

The AQM attitude is that we shouldn’t treat the measurement process as anything mystical or even in need of its own set of rules.