Perl and Unicode

#!/usr/bin/env perl
#
use strict;
use charnames ':full';
use utf8;

# First, let's print the source code.
open THIS, $0;
print $_ while (<THIS>);

# Get the vector elements sum. We use the Sigma greek letter.
sub Σ
{
    my ($accum) = shift;
    
    foreach(@_)
    {
      $accum += $_;  
    }
    return $accum;
}

# My Day is done!
# But Gauss would do it better!
# We can see that perl allows any
# Alphabet caracter to be used, but any symbol
# is reserverd. This is the case of integral symbols
# ∫, ∬, ∭, ∮, ∯, ∰, ∳, ∲. and even the Summantion sign ∑
# Note that this is not the greek sigma letter. Perl is smart, hum?

my @Ϯ = 1 .. 100; 
my $ΔU = Σ @Ϯ;  # Σ is not ∑. (Sigma and summantion sign).

print "The Summation from one to a handred is $ΔU.\n";

# Energy Funcion Ψ. 
# It goes from ± a radius around
# the center.
sub Ψ
{
    my ($α,$β,$γ) = @_[0..2];
    return  $α**2 + $β**2 + $γ**2;
}



# My runic letter Gar
my $ᚸ = Ψ(2.3, 234.0, 23.4);

# Listing day in Japanese, from Sunday to Saturday
my @Ա = qw/㈰ ㈪ ㈫ ㈬ ㈭ ㈮ ㈯/;

# A dictionary.
my %Ծ = 
(
    "㈰" => ["Sun", "Sunday"],
    "㈪"  => ["Moon", "Monday"],
    "㈫ " => ["Fire", "Tuesday"],
    "㈬"  => ["Water", "Wednesday"],
    "㈭"  => ["Wood", "Thursday"],
    "㈮"  => ["Metal", "Friday"],
    "㈯"  => ["Earth", "Saturday"],
);


# Now, lets print the sign for Astrological sign.

my $signs = join ", ", map { chr(ord("♈") + $_ - 1) } 1..12;

print "This is a list with the signs $signs.\n";

foreach my $Ʃ (@Ա)
{
    print "$Ʃ is the Japanese symbol for $Ծ{$Ʃ}->[0] element, also  $Ծ{$Ʃ}->[1] week\'s day.\n";
}