# Kernel crash after simple input of variable defintion

Fixed in 10.3.0

I have encountered a very surprising and annoying kernel crash:

xxx = (-((I*b[-3] + (a[3] + I*d[-3])/Sqrt[2])*(c[5] + (I*(I*a[3] + d[-3]))/Sqrt[2]))/2 - ((I*b[-4] + (a[4] + I*d[-4])/Sqrt[2])*(c[4] + (I*(I*a[2] + d[-2]))/Sqrt[2]))/2 - ((I*b[-5] + (a[5] + I*d[-5])/Sqrt[2])*(c[3] + (I*(I*a[1] + d[-1]))/Sqrt[2]))/2 + ((b[2] + (I*(a[-2] + I*d[2]))/Sqrt[2])*(I*c[-1] + (I*a[-3] + d[3])/Sqrt[2]))/2 + ((b[1] + (I*(a[-1] + I*d[1]))/Sqrt[2])*(I*c[-2] + (I*a[-4] + d[4])/Sqrt[2]))/2 + ((b[0] + (I*(a[0] + I*d[0]))/Sqrt[2])*(I*c[-3] + (I*a[-5] + d[5])/Sqrt[2]))/2)^2


When I evaluate this expression, and the output is not supressed, my kernel repeatably crashes.

I have Mathematica 9.0.1.0 under Windows 8 (version 6.3). Can somebody confirm this? Is this behaviour known? Has it been fixed in newer versions?

• no crash here Mma 10 Commented Jun 1, 2016 at 21:05
• Try restarting the kernel. There might be existing definitions of a, b, c, and d. Commented Jun 1, 2016 at 22:16
• Works fine on V10.4.1 running on OS X 10.10.2. Commented Jun 1, 2016 at 23:48
• I can verify that it crashes the kernel in version 9.0 for Windows, but only when input comes from the Front End, not in the standalone kernel. It seems to be fixed in later versions. Commented Jun 2, 2016 at 0:17