Why did Schrödinger pick a cat?
2 Answers
Erwin Schrödinger chose a cat for his famous thought experiment to illustrate the concept of quantum superposition and the difficulties of applying quantum mechanics to everyday objects. The thought experiment, now known as "Schrödinger's cat," was proposed in 1935 as part of a paper written with the intent of critiquing the Copenhagen interpretation of quantum mechanics.
Here's a more detailed breakdown of why Schrödinger picked a cat and the broader context:
### 1. **Quantum Superposition:**
- **Core Idea:** In quantum mechanics, particles can exist in a superposition of states, meaning they can be in multiple states at once until measured. For example, an electron can be in a superposition of spinning clockwise and counterclockwise until observed.
- **Schrödinger's Goal:** Schrödinger wanted to extend this idea to a macroscopic object (a cat, in this case) to challenge how quantum mechanics applies to everyday objects. He aimed to show that applying quantum principles to larger systems could lead to paradoxical or seemingly absurd situations.
### 2. **The Cat as a Representative Object:**
- **Why a Cat?:** Schrödinger chose a cat because it is a familiar, everyday object that everyone could understand. The idea of a cat being both alive and dead simultaneously was intended to highlight the paradox and absurdity when quantum mechanics is applied to larger systems.
- **Illustration of Paradox:** In the thought experiment, a cat is placed in a sealed box with a mechanism involving a radioactive atom, a Geiger counter, and a vial of poison. If the Geiger counter detects radiation (due to the radioactive atom decaying), the vial breaks and the cat dies. If no radiation is detected, the cat remains alive. According to quantum mechanics, until the box is opened and an observation is made, the atom is in a superposition of decayed and not decayed states, and consequently, the cat is in a superposition of being both alive and dead.
### 3. **Critique of Quantum Mechanics:**
- **The Paradox:** Schrödinger’s thought experiment illustrates the “measurement problem” in quantum mechanics. It questions how and when a quantum superposition of states collapses into a definite state when dealing with macroscopic objects.
- **Purpose:** Schrödinger used this paradox to highlight what he saw as an issue with the Copenhagen interpretation, which suggests that a system remains in superposition until it is observed. He aimed to show that applying quantum mechanics to everyday objects leads to paradoxical and counterintuitive conclusions.
### 4. **Broader Implications:**
- **Philosophical Questions:** The thought experiment raises questions about the nature of reality and observation. It challenges our understanding of how quantum effects translate to the macroscopic world and what it means for a system to have definite properties.
- **Ongoing Discussions:** Schrödinger's cat has since become a central topic in discussions about quantum mechanics, measurement theory, and the nature of reality. It has also influenced popular science and discussions about the interpretation of quantum phenomena.
In summary, Schrödinger picked a cat to dramatize the strange and seemingly absurd implications of applying quantum superposition to everyday objects. The choice of a cat made the paradox more relatable and vivid, illustrating the challenges and paradoxes inherent in quantum mechanics.
Here's a more detailed breakdown of why Schrödinger picked a cat and the broader context:
### 1. **Quantum Superposition:**
- **Core Idea:** In quantum mechanics, particles can exist in a superposition of states, meaning they can be in multiple states at once until measured. For example, an electron can be in a superposition of spinning clockwise and counterclockwise until observed.
- **Schrödinger's Goal:** Schrödinger wanted to extend this idea to a macroscopic object (a cat, in this case) to challenge how quantum mechanics applies to everyday objects. He aimed to show that applying quantum principles to larger systems could lead to paradoxical or seemingly absurd situations.
### 2. **The Cat as a Representative Object:**
- **Why a Cat?:** Schrödinger chose a cat because it is a familiar, everyday object that everyone could understand. The idea of a cat being both alive and dead simultaneously was intended to highlight the paradox and absurdity when quantum mechanics is applied to larger systems.
- **Illustration of Paradox:** In the thought experiment, a cat is placed in a sealed box with a mechanism involving a radioactive atom, a Geiger counter, and a vial of poison. If the Geiger counter detects radiation (due to the radioactive atom decaying), the vial breaks and the cat dies. If no radiation is detected, the cat remains alive. According to quantum mechanics, until the box is opened and an observation is made, the atom is in a superposition of decayed and not decayed states, and consequently, the cat is in a superposition of being both alive and dead.
### 3. **Critique of Quantum Mechanics:**
- **The Paradox:** Schrödinger’s thought experiment illustrates the “measurement problem” in quantum mechanics. It questions how and when a quantum superposition of states collapses into a definite state when dealing with macroscopic objects.
- **Purpose:** Schrödinger used this paradox to highlight what he saw as an issue with the Copenhagen interpretation, which suggests that a system remains in superposition until it is observed. He aimed to show that applying quantum mechanics to everyday objects leads to paradoxical and counterintuitive conclusions.
### 4. **Broader Implications:**
- **Philosophical Questions:** The thought experiment raises questions about the nature of reality and observation. It challenges our understanding of how quantum effects translate to the macroscopic world and what it means for a system to have definite properties.
- **Ongoing Discussions:** Schrödinger's cat has since become a central topic in discussions about quantum mechanics, measurement theory, and the nature of reality. It has also influenced popular science and discussions about the interpretation of quantum phenomena.
In summary, Schrödinger picked a cat to dramatize the strange and seemingly absurd implications of applying quantum superposition to everyday objects. The choice of a cat made the paradox more relatable and vivid, illustrating the challenges and paradoxes inherent in quantum mechanics.
Erwin Schrödinger's choice of a cat in his famous thought experiment, known as Schrödinger's Cat, was both a practical and a philosophical decision. Here's why he picked a cat:
### 1. **Illustrative Purpose**:
Schrödinger’s primary aim was to highlight the paradoxes and implications of quantum mechanics. The cat was a convenient way to illustrate the concept of superposition in a more tangible, everyday context. Quantum mechanics often deals with phenomena at microscopic scales, like electrons or photons, which are difficult to visualize. Using a cat made the abstract principles more relatable and easier to understand for those unfamiliar with quantum physics.
### 2. **Contrast with Classical Intuition**:
Schrödinger chose a cat to show the absurdity of applying quantum superposition to macroscopic objects. In the thought experiment, the cat is placed in a sealed box with a mechanism that can randomly kill it, depending on the decay of a radioactive atom. According to quantum mechanics, until the box is opened and observed, the cat is considered to be in a superposition of being both alive and dead simultaneously. This scenario starkly contrasts with our classical intuition, which suggests that macroscopic objects, like cats, should not be in such superpositions.
### 3. **Philosophical Implications**:
The use of a cat also serves to explore philosophical questions about observation and reality. Schrödinger wanted to challenge the Copenhagen interpretation of quantum mechanics, which suggests that quantum systems don't have definite properties until they are measured. By using a cat, Schrödinger emphasized the paradox that arises when quantum mechanics' probabilistic nature is applied to everyday objects, raising questions about the nature of reality and observation.
### 4. **Practicality and Simplicity**:
The choice of a cat is somewhat arbitrary, but it serves a practical purpose. A cat is a well-known and easily visualizable object. Schrödinger’s aim was not to experiment on actual cats but to use a thought experiment to provoke discussion and deeper understanding of quantum mechanics. The cat was not meant to be a real experiment but a hypothetical construct to make a complex theory more comprehensible.
### 5. **Humor and Provocation**:
Schrödinger was also known for his wit and critical thinking. By choosing a cat, he might have been using a bit of humor and provocation to challenge the scientific community's views and stimulate debate about the fundamental interpretations of quantum mechanics.
In summary, Schrödinger's choice of a cat was a strategic one to vividly illustrate the peculiarities of quantum superposition and provoke thought about the interpretation of quantum mechanics in the macroscopic world. It wasn't about the cat itself but rather about using it as a tool to discuss and critique the conceptual foundations of quantum theory.
### 1. **Illustrative Purpose**:
Schrödinger’s primary aim was to highlight the paradoxes and implications of quantum mechanics. The cat was a convenient way to illustrate the concept of superposition in a more tangible, everyday context. Quantum mechanics often deals with phenomena at microscopic scales, like electrons or photons, which are difficult to visualize. Using a cat made the abstract principles more relatable and easier to understand for those unfamiliar with quantum physics.
### 2. **Contrast with Classical Intuition**:
Schrödinger chose a cat to show the absurdity of applying quantum superposition to macroscopic objects. In the thought experiment, the cat is placed in a sealed box with a mechanism that can randomly kill it, depending on the decay of a radioactive atom. According to quantum mechanics, until the box is opened and observed, the cat is considered to be in a superposition of being both alive and dead simultaneously. This scenario starkly contrasts with our classical intuition, which suggests that macroscopic objects, like cats, should not be in such superpositions.
### 3. **Philosophical Implications**:
The use of a cat also serves to explore philosophical questions about observation and reality. Schrödinger wanted to challenge the Copenhagen interpretation of quantum mechanics, which suggests that quantum systems don't have definite properties until they are measured. By using a cat, Schrödinger emphasized the paradox that arises when quantum mechanics' probabilistic nature is applied to everyday objects, raising questions about the nature of reality and observation.
### 4. **Practicality and Simplicity**:
The choice of a cat is somewhat arbitrary, but it serves a practical purpose. A cat is a well-known and easily visualizable object. Schrödinger’s aim was not to experiment on actual cats but to use a thought experiment to provoke discussion and deeper understanding of quantum mechanics. The cat was not meant to be a real experiment but a hypothetical construct to make a complex theory more comprehensible.
### 5. **Humor and Provocation**:
Schrödinger was also known for his wit and critical thinking. By choosing a cat, he might have been using a bit of humor and provocation to challenge the scientific community's views and stimulate debate about the fundamental interpretations of quantum mechanics.
In summary, Schrödinger's choice of a cat was a strategic one to vividly illustrate the peculiarities of quantum superposition and provoke thought about the interpretation of quantum mechanics in the macroscopic world. It wasn't about the cat itself but rather about using it as a tool to discuss and critique the conceptual foundations of quantum theory.