StudentsEducators

Schrödinger’s Cat Paradox

Schrödinger’s Cat is a thought experiment proposed by physicist Erwin Schrödinger in 1935 to illustrate the concept of superposition in quantum mechanics. In this scenario, a cat is placed in a sealed box with a radioactive atom, a Geiger counter, and a vial of poison. If the atom decays, the Geiger counter triggers the release of the poison, resulting in the cat's death. According to quantum mechanics, until the box is opened and observed, the cat is considered to be in a superposition state—simultaneously alive and dead. This paradox highlights the strangeness of quantum mechanics, particularly the role of the observer in determining the state of a system, and raises questions about the nature of reality and measurement in the quantum realm.

Other related terms

contact us

Let's get started

Start your personalized study experience with acemate today. Sign up for free and find summaries and mock exams for your university.

logoTurn your courses into an interactive learning experience.
Antong Yin

Antong Yin

Co-Founder & CEO

Jan Tiegges

Jan Tiegges

Co-Founder & CTO

Paul Herman

Paul Herman

Co-Founder & CPO

© 2025 acemate UG (haftungsbeschränkt)  |   Terms and Conditions  |   Privacy Policy  |   Imprint  |   Careers   |  
iconlogo
Log in

Computational Social Science

Computational Social Science is an interdisciplinary field that merges social science with computational methods to analyze and understand complex social phenomena. By utilizing large-scale data sets, often derived from social media, surveys, or public records, researchers can apply computational techniques such as machine learning, network analysis, and simulations to uncover patterns and trends in human behavior. This field enables the exploration of questions that traditional social science methods may struggle to address, emphasizing the role of big data in social research. For instance, social scientists can model interactions within social networks to predict outcomes like the spread of information or the emergence of social norms. Overall, Computational Social Science fosters a deeper understanding of societal dynamics through quantitative analysis and innovative methodologies.

Xgboost

Xgboost, short for eXtreme Gradient Boosting, is an efficient and scalable implementation of gradient boosting algorithms, which are widely used for supervised learning tasks. It is particularly known for its high performance and flexibility, making it suitable for various data types and sizes. The algorithm builds an ensemble of decision trees in a sequential manner, where each new tree aims to correct the errors made by the previously built trees. This is achieved by minimizing a loss function using gradient descent, which allows it to converge quickly to a powerful predictive model.

One of the key features of Xgboost is its regularization capabilities, which help prevent overfitting by adding penalties to the loss function for overly complex models. Additionally, it supports parallel computing, allowing for faster processing, and offers options for handling missing data, making it robust in real-world applications. Overall, Xgboost has become a popular choice in machine learning competitions and industry projects due to its effectiveness and efficiency.

Hahn-Banach

The Hahn-Banach theorem is a fundamental result in functional analysis, which extends the notion of linear functionals. It states that if ppp is a sublinear function and fff is a linear functional defined on a subspace MMM of a normed space XXX such that f(x)≤p(x)f(x) \leq p(x)f(x)≤p(x) for all x∈Mx \in Mx∈M, then there exists an extension of fff to the entire space XXX that preserves linearity and satisfies the same inequality, i.e.,

f~(x)≤p(x)for all x∈X.\tilde{f}(x) \leq p(x) \quad \text{for all } x \in X.f~​(x)≤p(x)for all x∈X.

This theorem is crucial because it guarantees the existence of bounded linear functionals, allowing for the separation of convex sets and facilitating the study of dual spaces. The Hahn-Banach theorem is widely used in various fields such as optimization, economics, and differential equations, as it provides a powerful tool for extending solutions and analyzing function spaces.

Hahn-Banach Separation Theorem

The Hahn-Banach Separation Theorem is a fundamental result in functional analysis that deals with the separation of convex sets in a vector space. It states that if you have two disjoint convex sets AAA and BBB in a real or complex vector space, then there exists a continuous linear functional fff and a constant ccc such that:

f(a)≤c<f(b)∀a∈A, ∀b∈B.f(a) \leq c < f(b) \quad \forall a \in A, \, \forall b \in B.f(a)≤c<f(b)∀a∈A,∀b∈B.

This theorem is crucial because it provides a method to separate different sets using hyperplanes, which is useful in optimization and economic theory, particularly in duality and game theory. The theorem relies on the properties of convexity and the linearity of functionals, highlighting the relationship between geometry and analysis. In applications, the Hahn-Banach theorem can be used to extend functionals while maintaining their properties, making it a key tool in many areas of mathematics and economics.

Rydberg Atom

A Rydberg atom is an atom in which one or more electrons are excited to very high energy levels, leading to a significant increase in the atom's size and properties. These atoms are characterized by their high principal quantum number nnn, which can be several times larger than that of typical atoms. The large distance of the outer electron from the nucleus results in unique properties, such as increased sensitivity to external electric and magnetic fields. Rydberg atoms exhibit strong interactions with each other, making them valuable for studies in quantum mechanics and potential applications in quantum computing and precision measurement. Their behavior can often be described using the Rydberg formula, which relates the wavelengths of emitted or absorbed light to the energy levels of the atom.

Harberger Triangle

The Harberger Triangle is a concept in public economics that illustrates the economic inefficiencies resulting from taxation, particularly on capital. It is named after the economist Arnold Harberger, who highlighted the idea that taxes create a deadweight loss in the market. This triangle visually represents the loss in economic welfare due to the distortion of supply and demand caused by taxation.

When a tax is imposed, the quantity traded in the market decreases from Q0Q_0Q0​ to Q1Q_1Q1​, resulting in a loss of consumer and producer surplus. The area of the Harberger Triangle can be defined as the area between the demand and supply curves that is lost due to the reduction in trade. Mathematically, if PdP_dPd​ is the price consumers are willing to pay and PsP_sPs​ is the price producers are willing to accept, the loss can be represented as:

Deadweight Loss=12×(Q0−Q1)×(Ps−Pd)\text{Deadweight Loss} = \frac{1}{2} \times (Q_0 - Q_1) \times (P_s - P_d)Deadweight Loss=21​×(Q0​−Q1​)×(Ps​−Pd​)

In essence, the Harberger Triangle serves to illustrate how taxes can lead to inefficiencies in markets, reducing overall economic welfare.