Fourth-level heading: Single-line equations.

Below we have single-line equations with numbers; this is the most common type of equation in <#42#>Physical Review<#42#>:

#math84#

χ₊(p)#tex2html_wrap_indisplay783##tex2html_wrap_indisplay784#2|#tex2html_wrap_indisplay785#|(|#tex2html_wrap_indisplay786#| + p_z)#tex2html_wrap_indisplay789##tex2html_wrap_indisplay790##tex2html_wrap_indisplay791##tex2html_wrap_indisplay792# ,

(1)

#math85#

#tex2html_wrap_indisplay794##tex2html_wrap_indisplay795#234567890abc123αβγδ1234556αβ#tex2html_wrap_indisplay796##tex2html_wrap_indisplay797#.

(2)

Note the open one in Eq. (#one#59>).

Not all numbered equations will fit within a narrow column this way. The equation number will move down automatically if it cannot fit on the same line with a one-line equation:

#math86#

#tex2html_wrap_indisplay799#ab12345678abc123456abcdefαβγδ1234556αβ#tex2html_wrap_indisplay800##tex2html_wrap_indisplay801#.

(3)

When the 15 command is used [cf. input for Eq. (#one#64>)], the equation can be referred to in text without your knowing the equation number that TEX will assign to it. Just use 16, where 17 is the same name that you used in the 18 command.

The 19 and 20 commands will set displayed math flush left and flush right, respectively. Just insert the 21 or 22 command before the displayed math begins. For example, here is an equation flushed left:

#math87#

#tex2html_wrap_indisplay803#ab12345678bcdefαβγδ1234556αβ#tex2html_wrap_indisplay804##tex2html_wrap_indisplay805#.

(4)

You shouldn't need 23 and 24 very often.

If you have a single-line equation that you don't want numbered, you can use the <#361#>#math88#\[<#361#>, <#362#>#math89#\]<#362#> format:

#math90#

g⁺g⁺→g⁺g⁺g⁺g⁺...~,~~q⁺q⁺→q⁺g⁺g⁺...~.