Epsilon Symbol ε Ε

Get both uppercase (Ε) and lowercase (ε) epsilon symbols. Easy to copy and paste, with complete information about usage and typing methods.

What is the Epsilon Symbol?

Lowercase Epsilon (ε)

  • Unicode: U+03B5
  • HTML Code: ε
  • Aliases: Small Letter Epsilon, Lunate Epsilon, Lower Case Epsilon
  • Pronunciation: /ˈɛpsɪlɒn/

Description

The lowercase epsilon (ε) is the fifth letter of the Greek alphabet, representing the 'e' sound in Greek. Its form evolved from the Phoenician letter He, and it has become one of the most widely used Greek letters in various scientific fields. In modern Greek, epsilon represents the mid front unrounded vowel /e/. The symbol has gained significant importance in mathematics and sciences, where it often represents small quantities or error terms. The lowercase epsilon has two main typographical forms: - The lunate form (ε) - most commonly used in mathematics and science - The traditional form (ϵ) - sometimes used in typography and traditional Greek texts

Historical Background

Derived from the Phoenician letter He around 800 BCE, epsilon has maintained its position as the fifth letter throughout the evolution of the Greek alphabet.

Uppercase Epsilon (Ε)

  • Unicode: U+0395
  • HTML Code: Ε
  • Aliases: Capital Letter Epsilon, Upper Case Epsilon, Capital E
  • Pronunciation: /ˈɛpsɪlɒn/

Description

The uppercase epsilon (Ε) represents the capital form of the fifth letter in the Greek alphabet. In ancient Greek inscriptions, it appeared as a reversed 'E' and gradually evolved into its current form. While less commonly used in scientific notation compared to its lowercase counterpart, the uppercase epsilon maintains important roles in: - Greek language and literature - Mathematical set theory - Chemical nomenclature - Institutional logos and symbols

Historical Background

The uppercase epsilon evolved from the Phoenician He, initially written as "𐤄". Its modern form closely resembles the Latin letter E, though they developed independently.

How to Type Epsilon Symbol

Windows

Alt Code

Hold Alt and type 238 for ε (lowercase) or Alt + 917 for Ε (uppercase)

Note: Works on all Windows versions with a numeric keypad

Character Map

  1. Press Windows + R
  2. Type "charmap" and press Enter
  3. Select "Greek" from the Font dropdown
  4. Locate and double-click epsilon
  5. Click "Copy" to copy the symbol

Note: Useful for accessing both forms of epsilon and other Greek letters

Word/Office

  1. Click Insert > Symbol > More Symbols
  2. Select "Greek" from the Subset dropdown
  3. Find and select epsilon
  4. Click "Insert" or set up a shortcut

Note: Available in all Microsoft Office applications

Unicode Input

Hold Alt + X after typing 03B5 for ε or 0395 for Ε

Note: Works in most modern text editors and word processors

macOS

Keyboard Shortcut

Option + k for ε (lowercase)

Note: Quick and easy method for the lowercase symbol

Character Viewer

  1. Press Control + Command + Space
  2. Search for "epsilon"
  3. Click the desired symbol to insert

Note: Provides access to all Greek letters and variants

Greek Keyboard

  1. Open System Preferences > Keyboard > Input Sources
  2. Click + and add "Greek"
  3. Use the keyboard viewer to locate epsilon

Note: Useful for typing multiple Greek letters

Linux

Compose Key

Compose > e > e for ε

Note: Requires compose key setup

Unicode Input

Ctrl + Shift + U, then type 03B5 for ε or 0395 for Ε

Note: Works in most Linux distributions

Mobile Devices

iOS

  1. Hold down "e" on the keyboard
  2. Slide to select ε from the popup menu
  3. Alternative: Use Greek keyboard from Settings

Note: Available on iPhone and iPad

Android

  1. Long-press "e" on Gboard
  2. Select ε from the popup
  3. Alternative: Install Greek keyboard

Note: May vary by keyboard app and Android version

Common Uses of Epsilon Symbol

Mathematics

In mathematics, the epsilon symbol serves multiple crucial functions across different areas:

Calculus

Represents an arbitrarily small positive number in limit definitions

For any ε > 0, there exists δ > 0 such that...

Set Theory

Denotes set membership

x ∈ A means "x is an element of set A"

Analysis

Used in ε-δ definitions of limits and continuity

|f(x) - L| < ε whenever |x - a| < δ

Number Theory

Represents small error terms in approximations

π(x) = li(x) + O(x·exp(-c√(ln x)))

Physics

Epsilon plays vital roles across various branches of physics:

Electromagnetics

ε₀ represents vacuum permittivity

ε₀ ≈ 8.85 × 10⁻¹² F/m

Mechanics

Represents strain in materials

ε = ΔL/L₀ (longitudinal strain)

Thermodynamics

Denotes emissivity of materials

0 ≤ ε ≤ 1 for any real surface

Quantum Physics

Represents energy levels and states

εₙ = -13.6 eV/n² (hydrogen energy levels)

Economics

In economics, epsilon is commonly used in various analytical contexts:

Elasticity

Price elasticity of demand

ε = (ΔQ/Q)/(ΔP/P)

Econometrics

Error term in regression models

Y = β₀ + β₁X + ε

Efficiency Analysis

Technical efficiency measures

0 ≤ ε ≤ 1 for efficiency scores

Computer Science

Epsilon has several important applications in computer science:

Automata Theory

Represents empty string/transition

ε-NFA (Non-deterministic Finite Automaton with ε-moves)

Algorithms

Error tolerance in numerical computations

while |x - y| > ε do...

Machine Learning

Learning rate and convergence criteria

if loss < ε then stop training

Frequently Asked Questions

What is the difference between ε and Ε?

The lowercase epsilon (ε) and uppercase epsilon (Ε) are two forms of the same Greek letter. While both represent the same letter, they have different uses. The lowercase ε is more commonly used in mathematical and scientific notation, particularly for representing small quantities or error terms. The uppercase Ε is primarily used at the beginning of sentences in Greek text and in formal titles or acronyms.

Why can't I see the epsilon symbol on my device?

If you can't see the epsilon symbol, it might be due to font support issues on your device. Most modern devices and browsers support Greek characters, but you might need to: 1. Update your system fonts 2. Try a different web browser 3. Ensure your device's character encoding is set to UTF-8 4. Install a font that supports Greek characters

How do I type epsilon in Microsoft Word?

There are several ways to type epsilon in Microsoft Word: 1. Use the Insert Symbol feature (Insert > Symbol > More Symbols) 2. Use Alt codes: Alt + 238 for ε (lowercase) 3. Use the equation editor and type \epsilon 4. Set up an AutoCorrect entry for quick access

What's the meaning of epsilon in mathematics?

In mathematics, epsilon (ε) has several important meanings: 1. In calculus, it represents an arbitrarily small positive number 2. In set theory, it can denote set membership 3. In numerical analysis, it represents error terms or tolerance levels 4. In statistics, it often represents random error or residual terms

Can I use epsilon in programming?

Yes, epsilon is commonly used in programming, especially for: 1. Floating-point comparisons (e.g., Math.EPSILON in JavaScript) 2. Error tolerance in numerical algorithms 3. Machine learning convergence criteria 4. String processing in automata theory (ε-transitions)

Is epsilon used in other fields besides mathematics?

Yes, epsilon is widely used across various fields: 1. Physics: For electric permittivity and strain 2. Economics: In elasticity calculations 3. Engineering: For efficiency measurements 4. Chemistry: In extinction coefficients 5. Computer Science: For algorithm analysis

Complete Greek Alphabet

Letter Name Uppercase Lowercase
Alpha
Beta
Gamma
Delta
Epsilon
Zeta
Eta
Theta
Iota
Kappa
Lambda
Mu
Nu
Xi
Omicron
Pi
Rho
Sigma
Tau
Upsilon
Phi
Chi
Psi
Omega

Download Epsilon Symbol Images

Lowercase Epsilon (ε)

Lowercase Epsilon Symbol
SVG Format Download SVG
PNG Format Download PNG

Free for personal and commercial use. High-quality vector (SVG) and raster (PNG) formats available.

Uppercase Epsilon (Ε)

Uppercase Epsilon Symbol
SVG Format Download SVG
PNG Format Download PNG

Free for personal and commercial use. High-quality vector (SVG) and raster (PNG) formats available.

Usage Rights

All epsilon symbol images are provided free of charge and can be used for both personal and commercial purposes. The SVG format is vector-based and can be scaled to any size without loss of quality. PNG format is provided in high resolution (300 DPI) for optimal display quality.