Simply Connected
A Connected Domain is said to be simply connected (also called 1-connected) if any simpleclosed curve can be shrunk to a point continuously in the set. If the domain is Connected but notsimply, it is said to be Multiply Connected.
A Space 
is simply connected if it is 0-connected and if every Map from the 1-Sphere to extendscontinuously to a Map from the 2-Disk. In other words, every loop in the Space is contractible.
- Laurent Polynomial
- Laurent Series
- Law
- Law of Anomalous Numbers
- Law of Cancellation
- Law of Cosines
- Law of Large Numbers
- Law of Sines
- Law of Small Numbers
- Law of Tangents
- Law of Truly Large Numbers
- Lax-Milgram Theorem
- Lax Pair
- Layer
- Leading Digit Phenomenon
- Leading Order Analysis
- Leaf (Foliation)
- Leaf (Tree)
- Leakage
- Least Bound
- Least Common Multiple
- Least Deficient Number
- Least Period
- Least Prime Factor
- Least Squares Fitting