Charles Weibel's Home Page

Teaching Stuff (for more information, see Rutgers University, the Rutgers Math Department, and its Graduate Math Program.

Research papers & stuff: This is a link to some of my research papers. Here are my research interests and my Ph.D. Students.

Do you like the History of Mathematics? Here are some articles:

Definition: Proofiness is defined as "the art of using bogus mathematical arguments to prove something that you know in your heart is true — even when it's not." -Charles Seife

I am often busy editing the Journal of Pure and Applied Algebra (JPAA), the Annals of K-theory and the journals HHA and JHRS.

Note: The Journal of K-theory ceased publication in December 2014.
Link to submit to the Annals of K-theory

Please donate to the K-theory Foundation (a nonprofit organization)

Seminars I like:

Links to other WWW sites
Fun Question: How can you prove that 123456789098765432111 is a prime number?
note that 12345678987654321 = 111111111 x 111111111
Fun Facts about Mersenne primes: In 1644, a French monk named Marin Mersenne studied numbers of the form $N=2^p-1$, where p is prime, and published a list of 11 such numbers he claimed were prime numbers (he got two wrong). Such prime numbers are called Mersenne primes. The first few Mersenne primes are $3,7,31,127$ (corresponding to $p=2,3,5,7$), but not all numbers of the form $2^p-1$ are prime; Regius discovered in 1536 that p=11 gives the non-prime 2047=23*89.
The next few Mersenne primes are $8191,131071,524287$ (for $p=13,17,19$). The next few primes $p$ for which $2^p-1$ is not prime are p=23 and p=37 (discovered by Fermat in 1640), and p=29 (discovered by Euler in 1738).

Mersenne primes are the largest primes we know. By 2014, the list of the first 44 Mersenne primes was verified; we don't know what is the 45th smallest, even though a handful of larger Mersenne primes are known. For years, the Electronic Frontier Foundation (EFF) offered a $50,000 prize for the first known prime with over 10 million digits. The race to win this prize came down the wire in Summer 2008, as the 45th and 46th known Mersenne primes were discovered in within 2 weeks of each other by the UCLA Math Department (who won the prize) and an Electrical Engineer in Germany, respectively.
The largest known Mersenne primes are the 48th, which has 17 million digits and p=57,885,161; the 45th has 13 million digits and p=43,112,609. A new Mersenne prime was discovered in 2016 with p=74,207,281; it has 22 million digits. (Each prime $N=2^p-1$ has $p\log_{10}(2)$ digits.)
For more information, check out the Mersenne site.
Charles Weibel / weibel @ / May 31, 2015

MATHJAX test: $\partial y/\partial t=\partial y/\partial x$, $\sqrt2=1.4141$,      $\forall n\in\mathbb{N}, e^n\in \mathbb R$
If $f(t)=\int_t^1 dx/x$ then $f(t)\to\infty$ as $t\to\infty$

HTML 4 font rednering:   ∂y/∂t = ∂y/∂x   √2 =1.414
If f(t)= ∫t 1 dx/x then f(t) → ∞ as t → 0. This really means:   (∀ε ∈ℝ,  ε>0) (∃δ>0) f(δ) > 1/ε .
ℕ (natural numbers), ℤ (integers), ℚ (rationals), ℝ (reals), ℂ (complexes)
The ndash (–) is & #150; ,   & #8211; and & ndash; !   I prefer the longer —, which is & mdash; or & #151;.